{"id":1425,"date":"2025-10-22T12:23:24","date_gmt":"2025-10-22T19:23:24","guid":{"rendered":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/?page_id=1425"},"modified":"2026-04-03T09:51:33","modified_gmt":"2026-04-03T16:51:33","slug":"chapter-15-entomology","status":"publish","type":"page","link":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/chapter-15-entomology\/","title":{"rendered":"Chapter 15: Entomology"},"content":{"rendered":"<div class=\"wsu-hero wsu-width--full wsu-pattern--wsu-light-radial-left  wsu-hero--style-boxed \">\n\t<div class=\"wsu-hero__background\">\n\t\t<div class=\"wsu-image-frame wsu-image-frame--fill\">\n\t<img decoding=\"async\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/09\/AdobeStock_291165832.jpg\"\n\t\tsrcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/09\/AdobeStock_291165832.jpg 1350w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/09\/AdobeStock_291165832.jpg 300w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/09\/AdobeStock_291165832.jpg 1024w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/09\/AdobeStock_291165832.jpg 768w\"\n\t\tsizes=\"(max-width: 1350px) 100vw, 1350px\"\n\t\talt=\"The monarch butterfly on a flower.\"\n\t\tstyle=\"object-position: 67% 93%\"\n\t\t\/>\n<\/div>\n\t<\/div>\n\t<div class=\"wsu-hero__overlay\">\n\t<\/div>\n\t<div class=\"wsu-hero__content-wrapper\">\n\t\t<div class=\"wsu-hero__inner-content-wrapper\">\n\t\t\t\t\t\t<div class=\"wsu-hero__title-wrapper\">\n\t\t\t\t<h1 class=\"wsu-hero__title\">Entomology<\/h1>\t\t\t\t<div class=\"wsu-hero__caption\">Chapter 15<\/div>\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<div class=\"wsu-hero__content\">\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n<\/div>\n\n\n\n<p class=\"wsu-spacing-after--xsmall\"><strong>Michael R. Bush<\/strong>, Entomologist, Washington State Department of Agriculture Yakima County<\/p>\n\n\n\n<p class=\"wsu-spacing-after--xsmall\"><strong>Todd A. Murray<\/strong>, Director, Puyallup Research and Extension Center, Washington State University<\/p>\n\n\n\n<p class=\"wsu-spacing-after--xsmall\"><strong>Arthur L. Antonelli<\/strong>, Extension Entomologist Emeritus (deceased), Washington State University<\/p>\n\n\n\n<div style=\"height:10px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n<div class=\"wsu-row wsu-row--sidebar-right\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h2 class=\"wp-block-heading wsu-font-size--xlarge wsu-heading--style-marked wsu-spacing-after--xxmedium\" id=\"learning-objectives\">Learning Objectives<\/h2>\n\n\n\n<ul>\n<li>Recognize characteristic features of, and plant damage by, key pests in the garden.<\/li>\n\n\n\n<li>An appreciation of insects and their roles in plant pollination, predation of other organisms, and recycling of plant nutrients in the garden.<\/li>\n\n\n\n<li>Understand the life history of insects and how this contributes to their potential as plant, animal, and structural pests.<\/li>\n<\/ul>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h2 class=\"wp-block-heading\">Topics Covered<\/h2>\n\n\n\n<ul class=\"wsu-menu--style-sidebar\">\n<li><a href=\"#ch15-introduction\" data-type=\"internal\" data-id=\"#ch15-introduction\">Introduction<\/a><\/li>\n\n\n\n<li><a href=\"#ch15-arthropods\" data-type=\"internal\" data-id=\"#ch15-arthropods\">The Arthropods<\/a><\/li>\n\n\n\n<li><a href=\"#ch15-biology\" data-type=\"internal\" data-id=\"#ch15-biology\">Biology<\/a><\/li>\n\n\n\n<li><a href=\"#ch15-insect-pest-damage-id\" data-type=\"internal\" data-id=\"#ch15-insect-pest-damage-id\">Insect Pest Damage Identification<\/a><\/li>\n\n\n\n<li><a href=\"#ch15-insect-diversity\" data-type=\"internal\" data-id=\"#ch15-insect-diversity\">Insect Diversity and Natural History<\/a><\/li>\n\n\n\n<li><a href=\"#ch15-further-reading\" data-type=\"internal\" data-id=\"#ch15-further-reading\">Further Reading<\/a><\/li>\n<\/ul>\n\n<\/div>\r\n\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch15-introduction\">Introduction<\/h2>\n\n\n\n<p>The animal kingdom includes <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#b\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#b\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>beneficial organisms<\/strong> (opens in new window)<\/a> and <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#n\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>natural enemies<\/strong> (opens in new window)<\/a> as well as <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#k\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>key pests<\/strong> (opens in new window)<\/a> in the home landscape and garden. The animal kingdom is split into taxonomic units called phyla. This chapter focuses on <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#i\" target=\"_blank\"><strong>insects<\/strong> (opens in new window)<\/a>\u2014one of the units within the phylum Arthropoda.<\/p>\n\n\n<div class=\"wsu-callout wsu-border--color-vineyard wsu-callout--style-basic wsu-color-background--gray-5 wsu-border--add-left wsu-align-item--center wsu-spacing-after--large wsu-spacing-before--large wsu-max-width--xmedium\" >\r\n        \n\n<p class=\"has-text-align-center wsu-font-size--medium\">Entomology is the study of insects, from the Greek words <em>entomon<\/em> meaning \u201cinsect\u201d and <em>logia<\/em> meaning \u201cthe study of.\u201d Arthropoda translates as \u201cthose with jointed feet\u201d from the Greek word <em>arthron<\/em> meaning \u201ca joint\u201d and <em>podos<\/em> meaning \u201cfoot.\u201d<\/p>\n\n<\/div>\r\n\n\n\n<p class=\"wsu-spacing-after--xsmall\"><a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#a\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#a\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Arthropods<\/strong> (opens in new window)<\/a> are divided into clearly defined units called classes. There are about nine classes of arthropods, but only about four or five are important to gardeners. Those arthropods commonly found in home gardens include:<\/p>\n\n\n\n<ul>\n<li>Arachnida (spiders, mites, daddy long-legs)<\/li>\n\n\n\n<li>Diplopoda (millipedes)<\/li>\n\n\n\n<li>Chilopoda (centipedes)<\/li>\n\n\n\n<li>Symphyla (garden symphylans)<\/li>\n\n\n\n<li>Crustacea (sowbugs, pillbugs)<\/li>\n\n\n\n<li>Insecta (ants, beetles, aphids, bees, and others)<\/li>\n<\/ul>\n\n\n\n<p>As each of the classes listed are considered, home gardeners will recognize those external characteristics that separate these arthropods into these distinctive classes. This knowledge will help gardeners better <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#d\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>diagnose<\/strong> (opens in new window)<\/a> plant problems and identify key pests.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-01-1.jpg\" alt=\"A spider on a yellow flower.\" class=\"wp-image-3011\" width=\"300\" height=\"450\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-01-1.jpg 400w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-01-1-200x300.jpg 200w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><figcaption class=\"wp-element-caption\">Figure 1. Class Arachnida includes spiders like this grass spider. Most members of this class will have a cephalothorax with four pairs of legs and an abdomen. Photo by M. Asche.<\/figcaption><\/figure><\/div>\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch15-arthropods\">The Arthropods<\/h2>\n\n\n\n<p>Class Arachnida (i.e., <em>arachnids<\/em>) is represented by spiders (Figure 1), mites, ticks, daddy long-legs, and others. Spiders are anatomically distinctive within this class by having two body regions\u2014the <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>cephalothorax<\/strong> (opens in new window)<\/a> and an abdomen. Typically, as adults, arachnids have four pairs of legs attached to the cephalothorax. This class is variable in its feeding habits. All spiders are <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>predators<\/strong> (opens in new window)<\/a>; ticks and some mites are blood feeders, while other mites are plant feeders and thus key garden pests.<\/p>\n\n\n\n<p class=\"wsu-spacing-after--large\">Class Diplopoda (Figure 2) contains arthropods commonly called millipedes. Millipedes are elongated with two visible body regions\u2014the head and body. The body segments tend to be rounded or \u201cblocky\u201d in cross-section. Most have 30 or more pairs of legs, and each body segment possesses two pairs of legs except for the first five or six segments that may have only one pair. They are slow moving and feed exclusively on fungi and decaying plant matter, thus making millipedes important <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#r\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#r\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>recyclers<\/strong> (opens in new window)<\/a> of dead plant tissue into the garden soil.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-02_Left.jpg\" alt=\"Close-up of millipede.\n\n\" class=\"wp-image-3012\" width=\"546\" height=\"365\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-02_Left.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-02_Left-300x200.jpg 300w\" sizes=\"(max-width: 546px) 100vw, 546px\" \/><figcaption class=\"wp-element-caption\">Figure 2. Class Diplopoda includes the millipedes that possess two pairs of legs per segment, except for the first five or six segments. Photos by M. Peterson (left) and M. Ashe (right).<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-02_Right.jpg\" alt=\"Close-up of underside of millipede.\" class=\"wp-image-3013\" width=\"546\" height=\"367\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-03-1.jpg\" alt=\"Close-up of red centipede.\" class=\"wp-image-3016\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-03-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-03-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 3. Class Chilopoda are the centipedes. Centipedes have a single pair of legs on each body segment and the body appears flat in cross-section. Photo by M. Peterson.<\/figcaption><\/figure><\/div>\n\n\n<p class=\"wsu-spacing-before--large\">Class Chilopoda are the centipedes (Figure 3) that somewhat resemble millipedes but differ in having a single pair of legs on each body segment and typically appear flat in cross-section. Centipedes are often fast-moving, which aids them in their predacious lifestyle.<\/p>\n\n\n\n<p>Class Symphylan is a very small group whose members resemble tiny centipedes (Figure 4). They have long antennae, two flattened body regions (a head and body), and up to 12 pairs of legs as adults. They have no eyes (the other classes generally do), but are better suited to navigate the soil environment. The garden symphylan or garden \u201ccentipede\u201d is an increasingly reemerging pest that feeds on the roots of vegetable plants. Historically garden symphylans were serious pests in the Pacific Northwest, but it is believed that past insecticide use (using DDT, for example) kept symphylans under a level of control. Since those insecticides are no longer used, garden symphylan pest problems are becoming more common again. Garden symphylans are often associated with high organic matter in the soil.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-04-1.jpg\" alt=\"Close-up of garden symphylan.\" class=\"wp-image-3018\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-04-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-04-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 4. Arthropods in the class Symphylan, like this garden symphylan, resemble tiny centipedes. Photo by Whitney Cranshaw, Colorado State University, Bugwood.org.<\/figcaption><\/figure><\/div>\n\n\n<p>Class Crustacea (e.g., crabs, shrimp, and lobster) has only two groups that live entirely on land, and both are of interest to the gardener\u2014sowbugs and pillbugs (Figure 5). Both sowbugs and pillbugs are oval with a hard, convex outer shell made up of several plates. A clear difference between the two is that pillbugs can roll up in a ball like an armadillo when disturbed while sowbugs cannot. These invertebrates are scavengers that require moisture for their survival and thus are known for their association with damp habitats. They feed on decaying plant material like rotting fruit or wood. They are frequently blamed for damage caused by other creatures such as slugs. Fermenting plant wounds can attract sowbugs and pillbugs. On rare occasions, these crustaceans will attack healthy plants and plant seedlings.<\/p>\n\n\n\n<p>Insects are in the class Insecta and are distinguishable from all other arthropod classes by possessing three distinct body segments. Since insects are the most important arthropod encountered in home gardens, more discussion on their biology, function, and external features follows.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-05-1.jpg\" alt=\"Close-up of pillbug.\" class=\"wp-image-3021\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-05-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-05-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 5. Class Crustacea includes sowbugs and pillbugs. Both crustaceans are oval with a hard, convex outer shell, but sowbugs cannot curl up into a ball like pillbugs. Photo by M. Asche.<\/figcaption><\/figure><\/div>\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch15-biology\">Biology<\/h2>\n\n\n\n<p>Arthropods are invertebrates; that is, they do not have a backbone or internal skeleton. Arthropods are unique from other animal phyla because they have a chitinous exoskeleton, <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#b\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#b\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>bilateral symmetry<\/strong> (opens in new window)<\/a>, and conspicuous body segmentation.<\/p>\n\n\n\n<p>Possession of an exoskeleton presents unique challenges and benefits. The physics of an exoskeleton and internal muscle attachments limit the size that insects can achieve. On the other hand, the exoskeleton can bestow an inordinate level of strength for individual insects.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><em>Anatomy<\/em><\/h3>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-06_Crop-bottom-2.jpg\" alt=\"Black-and-white labeled diagram of an insect, side view, showing major external body parts. The insect has three main body regions: head, thorax, and abdomen. Head: Features include two antennae, a pair of large compound eyes, two smaller simple eyes, and mouthparts. Thorax: Attached are three pairs of legs\u2014foreleg, midleg, and hindleg. Two pairs of wings extend upward: the forewing (front) and hindwing (rear). Abdomen: Composed of segmented sections with visible spiracles (air holes) along the sides for breathing. Text under the figure reads: \u201cFig. 5. The insect design: parts of an insect.\u201d The diagram provides a clear overview of insect anatomy, with each labeled structure pointing to its correct location.\" class=\"wp-image-3030\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-06_Crop-bottom-2.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-06_Crop-bottom-2-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 6. Body parts of an insect. Image: WSU.<\/figcaption><\/figure><\/div>\n\n\n<p>Insects differ from other arthropods in that they have three distinctive body regions\u2014the head, <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#t\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#t\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>thorax<\/strong> (opens in new window)<\/a>, and abdomen (Figure 6). At some point in their development (usually as mature adults), insects will possess three pairs of legs attached to the thorax. Many insects also possess one or two pairs of wings attached to the thorax. The <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>primitive insects<\/strong> (opens in new window)<\/a>, such as springtails, firebrats, and silverfish, never evolved wings but possess the other characteristics unique to the insect class.<\/p>\n\n\n\n<p>Internally, the insect\u2019s thorax is heavily muscled to assist in locomotion, such as walking, climbing, jumping, and flight. Most of the digestive, excretory, and reproductive systems are found within the abdomen. The circulatory system is open with fluids that bathe the organs and muscles with the aid of a dorsal aortic \u201cheart.\u201d The insects\u2019 \u201cfluid\u201d or <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#h\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#h\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>hemolymph<\/strong> (opens in new window)<\/a> has many functions, one of which is to serve as hydraulics during molting and the transformation from one growth stage to another induced by hormones, also moved through the hemolymph. Movement of oxygen is through a unique respiratory system whereby tubes or trachea carry air from the surface of the exoskeleton, through breathing holes called <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>spiracles<\/strong> (opens in new window)<\/a>, directly to the cells of muscles and organs.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><em>Growth and Development<\/em><\/h3>\n\n\n\n<p>Being constrained by an external skeleton (exoskeleton) causes insects to appear to grow in periodic spurts. Unlike humans and other organisms with an internal skeleton, insects first need to break down their exoskeleton before they can grow. Enzymes and other chemistries help break down the old exoskeleton while at the same time forming a new and larger exoskeleton. This process is mediated through hormones and finally accomplished by molting or the shedding of the exoskeleton. Each developmental or growth stage between molts is called an <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#i\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#i\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>instar<\/strong> (opens in new window)<\/a>. Insects are vulnerable to environmental changes, predation, and even injury during each molt.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-07_Crop-bottom-1.jpg\" alt=\"Black-and-white diagram showing the gradual or simple metamorphosis of a bug. Three life stages are illustrated from left to right: Eggs: Two elongated oval shapes, representing the initial stage. Nymph: A smaller version of the adult bug, with legs and body segments visible but lacking fully developed wings. An arrow points from eggs to nymph. Adult: A fully developed bug with large wings covering most of its body, longer legs, and more pronounced body structure. An arrow points from nymph to adult. Text below the image reads: \u201cMetamorphosis of a bug\u201d and \u201cFig. 6. Gradual or simple metamorphosis.\u201d This figure demonstrates how the insect develops gradually, without a pupal stage, progressing directly from nymph to adult.\" class=\"wp-image-3031\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-07_Crop-bottom-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-07_Crop-bottom-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 7. Progression of an insect\u2019s bodily changes as it goes through simple metamorphosis. Image: WSU.<\/figcaption><\/figure><\/div>\n\n\n<p>As insects mature, they go through a process called <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#m\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#m\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>metamorphosis<\/strong> (opens in new window)<\/a>, which means \u201ca change in form.\u201d This change in form can appear quite radical and dramatic in some insects or simple and modest in others. Only the most primitive insects have no metamorphosis; thus, they are said to be ametabolous. This group includes the springtails and silverfish. The only change they undergo during development after hatching from the egg is an increase in body size and sexual maturity.<\/p>\n\n\n\n<p>Insects that undergo <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>simple metamorphosis<\/strong> (opens in new window)<\/a> change very little during development. They have three stages: the egg, <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#n\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#n\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>nymph<\/strong> (opens in new window)<\/a>, and adult (Figure 7). The nymphs develop wing buds early in their life, but functional wings do not appear until the adult stage. Nymphs usually resemble adults and have similar feeding habits. Cockroaches, earwigs, termites, lice, true bugs, and aphids are in this group.<\/p>\n\n\n\n<p>A small group of aquatic insects, including mayflies and dragonflies, are considered to undergo an intermediate form of metamorphosis. These insects change radically from the aquatic nymph, or <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#n\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#n\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>naiad<\/strong> (opens in new window)<\/a>, to the adult stage. The naiads are aquatic, while the adults are winged and terrestrial. This group of insects are rarely encountered in home gardens as they are specific to aquatic habitats.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-08_Crop-bottom-1.jpg\" alt=\"Black-and-white diagram showing the complete, or complex, metamorphosis of a moth. Four stages are illustrated: Egg: Small round object with textured surface, shown at the right. Larva: A caterpillar-like form with a segmented body, short legs near the head, and fleshy abdominal prolegs. Positioned at the bottom of the image. Pupa: An elongated case-like structure with visible segmentation, shown at the left. Adult: A moth with broad, patterned wings spread open, long antennae, and a slender body. Positioned at the top center. Arrows between the stages indicate progression from egg \u2192 larva \u2192 pupa \u2192 adult. Text beneath the figure reads: \u201cMetamorphosis of a moth\u201d and \u201cFig. 7. Complete or complex metamorphosis.\u201d This figure demonstrates the four distinct stages of complete metamorphosis: egg, larva, pupa, and adult.\" class=\"wp-image-3033\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-08_Crop-bottom-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-08_Crop-bottom-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 8. Progression of a moth\u2019s bodily changes from egg to adult, through complex (complete) metamorphosis. Image: WSU.<\/figcaption><\/figure><\/div>\n\n\n<p>Other insects, like beetles, flies, fleas, moths, wasps, and ants, undergo <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" target=\"_blank\"><strong>complex metamorphosis<\/strong> (opens in new window)<\/a>. They develop through the stages of egg, <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#l\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#l\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>larva<\/strong> (opens in new window)<\/a>, <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>pupa<\/strong> (opens in new window)<\/a>, and adult (Figure 8). In garden pest <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>species<\/strong> (opens in new window)<\/a>, the larval stage is usually the most destructive, although the adult may be damaging. The pupa is a nonfeeding stage; in most cases, it is also nonmobile. Complex metamorphosis is the most species rich type of metamorphosis. Complex metamorphosis allows insects to evolve features at different life stages to specialize in certain activities. Typically, the larval stage is specialized in feeding, while the adult stage is specialized in mating and dispersing. In insects that undergo complex metamorphosis, the immature larvae do not resemble the adults.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-09-1.jpg\" alt=\"Close-up shot of tobacco budworm on a flower stalk.\" class=\"wp-image-3036\" width=\"300\" height=\"450\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-09-1.jpg 400w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-09-1-200x300.jpg 200w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><figcaption class=\"wp-element-caption\">Figure 9. A tobacco budworm, <em>Heliothis virescens<\/em>, captured in the act of damaging a flower bud. Notice the damage (holes, gouges) in the buds and signs (frass) on the leaves below the damaged buds. Photo by Sue Spain, Master Gardener volunteer, Yakima County.<\/figcaption><\/figure><\/div>\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch15-insect-pest-damage-id\">Insect Pest Damage Identification<\/h2>\n\n\n\n<p>For home gardeners, pest identification is based on recognizing the insect itself, as well as the symptoms of plant damage and signs of the pest (Figure 9). The insects causing the damage may have completed feeding and may no longer be present, so what often remains for identification purposes is usually just the damage that the insects created.<\/p>\n\n\n\n<p>Most insect plant damage is a result of the cutting, chewing, or sucking action during feeding. There are two basic types of mouthparts that cause plant damage\u2014chewing and sucking mouthparts, but there is also a wide range of intermediate types.<\/p>\n\n\n\n<p class=\"wsu-spacing-after--large\">Most pests with chewing mouthparts take bites from plant tissues, leaving holes or gouges behind. Sometimes this damage may appear rather generic (Figure 10). Short of catching the pest in the act, the accuracy of identification is marginal since the damage may be attributed to multiple species of beetles, cutworms, earwigs, sawfly larvae, and many other insects. Other, more distinct types of damage caused by insects with chewing mouthparts include leaf defoliation, leaf mining (Figure 11), stem boring, or leaf skeletonization (where only the leaf venation remains). These types of specific tissue damage can help gardeners identify the pest.<\/p>\n\n\n<div class=\"wsu-row wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-10_Left.jpg\" alt=\"Leaves with scattered, irregular holes.\" class=\"wp-image-3037\" width=\"538\" height=\"359\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-10_Left.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-10_Left-300x200.jpg 300w\" sizes=\"(max-width: 538px) 100vw, 538px\" \/><figcaption class=\"wp-element-caption\">Figure 10. Examples of plant damage caused by pests with chewing mouthparts. Damage from these pests appears as holes or gouges in plant tissues. Photos by T. Murray.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-10_Right.jpg\" alt=\"Close-up of patchwork leaf damage as irregular holes.\" class=\"wp-image-3038\" width=\"538\" height=\"359\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-10_Right.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-10_Right-300x200.jpg 300w\" sizes=\"(max-width: 538px) 100vw, 538px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-spacing-before--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-11_Left.jpg\" alt=\"Characteristic web tent covering a defoliated branch. Multiple caterpillars crawl outside.\" class=\"wp-image-3039\" width=\"540\" height=\"360\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-11_Left.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-11_Left-300x200.jpg 300w\" sizes=\"(max-width: 540px) 100vw, 540px\" \/><figcaption class=\"wp-element-caption\">Figure 11. Distinct types of chewing insect damage such as leaf defoliation caused by tent caterpillar feeding (top photo) and leaf mining done by immature moth larvae (bottom photo). Photos by M. Asche (top) and T. Murray (bottom).<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-11_Right.jpg\" alt=\"A patch of yellow tissue in otherwise green leaf tissue.\" class=\"wp-image-3040\" width=\"540\" height=\"360\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-11_Right.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-11_Right-300x200.jpg 300w\" sizes=\"(max-width: 540px) 100vw, 540px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n\n<p>Pests with sucking mouthparts usually leave evidence in the form of predictable plant symptoms due to toxins or enzymes in their saliva. These symptoms include tissue spotting or stippling, plant galling (Figure 12), leaf curling and distortions, needle drop, or catfacing. Once home gardeners learn to recognize these symptoms, problem diagnosis can sometimes be done without the presence of the pest.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-before--large wsu-spacing-after--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-12_Left.jpg\" alt=\"Left: Close-up of one leaf on a blueberry bush that is twisted and deformed.\" class=\"wp-image-3042\" width=\"538\" height=\"359\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-12_Left.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-12_Left-300x200.jpg 300w\" sizes=\"(max-width: 538px) 100vw, 538px\" \/><figcaption class=\"wp-element-caption\">Figure 12. Distinct types of sucking insect damage include deformed new plant growth from aphids feeding on blueberry (top photo) and these wasp-induced galls on underside of oak leaf (bottom photo). Photos by T. Murray (top) and M. Bush (bottom).<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-12_Right.jpg\" alt=\"Oak leaves on a table lays next to a quarter coin for scale. Multiple round, yellow galls cover the underside of the leaves.\" class=\"wp-image-3043\" width=\"538\" height=\"359\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-12_Right.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-12_Right-300x200.jpg 300w\" sizes=\"(max-width: 538px) 100vw, 538px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n\n<p>If you suspect that a particular insect is a pest and are attempting to accurately identify it, the external features and structures will help. This can be done by comparing the specimen with those in an office reference collection, as reference collections of garden pests and digital images (see the <a href=\"https:\/\/hortsense.cahnrs.wsu.edu\/\" data-type=\"URL\" target=\"_blank\" rel=\"noreferrer noopener\">WSU Hortsense (opens in new window)<\/a> website) are helpful. Alternatively, insect identification can also be done by using a <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#d\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#d\" target=\"_blank\"><strong>dichotomous key<\/strong> (opens in new window)<\/a>. Such keys are based on \u201ceither-or\u201d choices or couplets. If the key is well done and you interpret what you see correctly, you will arrive at the right choice in the identification key. The Amateur Entomologists\u2019 Society provides an example <a rel=\"noreferrer noopener\" href=\"https:\/\/www.amentsoc.org\/insects\/what-bug-is-this\/adult-key.html\" data-type=\"URL\" data-id=\"https:\/\/www.amentsoc.org\/insects\/what-bug-is-this\/adult-key.html\" target=\"_blank\">insect identification key (opens in new window)<\/a>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><em>Naming Insects<\/em><\/h3>\n\n\n\n<p>Technically, insects are named following the protocol shown in Table 1.<\/p>\n\n\n<span id=\"tablepress-88-description\" class=\"tablepress-table-description tablepress-table-description-id-88\">Table 1. Classification protocol for <em>Diabrotica undecimpunctata.<\/em><\/span>\n\n<table id=\"tablepress-88\" class=\"tablepress tablepress-id-88\" aria-describedby=\"tablepress-88-description\">\n<thead>\n<tr class=\"row-1 odd\">\n\t<th class=\"column-1\">Classification Level<\/th><th class=\"column-2\">Scientific Name<\/th><th class=\"column-3\">Common Name # 1<br \/>\n(Pacific Northwest)<\/th><th class=\"column-4\">Common Name #2<br \/>\n(Midwest)<\/th>\n<\/tr>\n<\/thead>\n<tbody class=\"row-hover\">\n<tr class=\"row-2 even\">\n\t<td class=\"column-1\">Phylum<\/td><td class=\"column-2\">Arthropoda<\/td><td class=\"column-3\"><span class=\"wsu-screen-reader-only\">Not applicable<\/span><\/td><td class=\"column-4\"><span class=\"wsu-screen-reader-only\">Not applicable<\/span><\/td>\n<\/tr>\n<tr class=\"row-3 odd\">\n\t<td class=\"column-1\">Class<\/td><td class=\"column-2\">Insecta<\/td><td class=\"column-3\">Insects<\/td><td class=\"column-4\">Insects<\/td>\n<\/tr>\n<tr class=\"row-4 even\">\n\t<td class=\"column-1\">Order<\/td><td class=\"column-2\">Coleoptera<\/td><td class=\"column-3\">Beetles<\/td><td class=\"column-4\">Beetles<\/td>\n<\/tr>\n<tr class=\"row-5 odd\">\n\t<td class=\"column-1\">Family<\/td><td class=\"column-2\">Chrysomelidae<\/td><td class=\"column-3\">Leaf Beetles<\/td><td class=\"column-4\">Rootworms<\/td>\n<\/tr>\n<tr class=\"row-6 even\">\n\t<td class=\"column-1\"><em>Genus<\/em><\/td><td class=\"column-2\"><em>Diabrotica<\/em><\/td><td class=\"column-3\">Spotted cucumber beetle<\/td><td class=\"column-4\">Southern corn rootworm<\/td>\n<\/tr>\n<tr class=\"row-7 odd\">\n\t<td class=\"column-1\"><em>Species<\/em><\/td><td class=\"column-2\"><em>undecimpunctata<\/em><\/td><td class=\"column-3\">Spotted cucumber beetle<\/td><td class=\"column-4\">Southern corn rootworm<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<!-- #tablepress-88 from cache -->\n\n\n\n<p class=\"wsu-spacing-before--large\">Home gardeners may be familiar with a pest\u2019s <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" target=\"_blank\"><strong>common name<\/strong> (opens in new window)<\/a> but not necessarily know the <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#g\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#g\" target=\"_blank\"><strong>genus<\/strong> (opens in new window)<\/a> and species name. It is important to realize that common names can sometimes lead to confusion.<\/p>\n\n\n\n<p>Please remember the importance of <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>scientific names<\/strong> (opens in new window)<\/a> to universal accuracy. While home gardeners in the Pacific Northwest (PNW) may recognize <em>Diabrotica undecimpunctata<\/em> as the spotted cucumber beetle that feeds on the leaves of cucumbers and beans, gardeners in the Midwest recognize the same beetle species as the southern corn rootworm, whose beetle larvae feed on the roots of young vegetable plants. In this case, the species is recognized as <em>D. undecimpunctata<\/em> regardless of where it is found and what it is feeding on.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-spacing-before--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-13_Left.jpg\" alt=\"Close-up of nearly translucent, light-yellow springtails. \" class=\"wp-image-3048\" width=\"540\" height=\"360\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-13_Left.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-13_Left-300x200.jpg 300w\" sizes=\"(max-width: 540px) 100vw, 540px\" \/><figcaption class=\"wp-element-caption\">Figure 13. The Collembola order includes the springtails. Associated with moist areas, they can be found in compost, and some springtails have a special appendage that slaps the ground and propels them though the air for a quick getaway. Photos by M. Bush.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-13_Right.jpg\" alt=\"Side view of brown Entomobryid springtail with hairy back and a long, forked appendage. \" class=\"wp-image-3049\" width=\"540\" height=\"360\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-13_Right.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-13_Right-300x200.jpg 300w\" sizes=\"(max-width: 540px) 100vw, 540px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wp-block-image wsu-spacing-before--xxmedium\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-14-1.jpg\" alt=\"Close-up of silverfish, which has three long anal cerci and two long antennae.\" class=\"wp-image-3051\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-14-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-14-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 14. A silverfish. Photo by M. Bush.<\/figcaption><\/figure><\/div>\n\n\n<h3 class=\"wp-block-heading\"><em>Major Insect Orders<\/em><\/h3>\n\n\n\n<p>There are over 27 orders of insects found in North America, but not all of them are encountered in PNW gardens.<\/p>\n\n\n\n<p class=\"wsu-spacing-after--default\"><strong><em>Collembola<\/em><\/strong>. Collembola are commonly known as springtails (Figure 13). These wingless insects are very small, almost microscopic, and do not undergo metamorphosis. They have chewing mouthparts. Many possess an appendage on their ventral side which acts as a spring to propel them through the air for a quick escape. Collembolans are abundant in moist conditions, hence the common reference to \u201cmoving piles of soot\u201d in excessively moist yards. They feed on decaying organic material, algae, bacteria, animal byproducts, and dead insects. As <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#d\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#d\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>decomposers<\/strong> (opens in new window)<\/a>, springtails are considered important to healthy garden soils, but there are a few species that feed on plants.<\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-before--large\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-15-1.jpg\" alt=\"A close-up, side view of a grasshopper.\" class=\"wp-image-3052\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-15-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-15-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 15. A clear-winged grasshopper, Camnula pellucida. Photo by M. Peterson.<\/figcaption><\/figure><\/div>\n\n\n<p class=\"wsu-spacing-before--default\"><strong><em>Thysanura<\/em><\/strong>. Thysanura include the silverfish and firebrats (Figure 14). Mature thysanurans are less than a half-inch long and covered with fine scales. They have chewing mouthparts, long antennae, and three long anal cerci. Thysanurans are ametabolous, and the adults are wingless. They feed on a wide range of material. Some feed on algae, lichens, and moss, and some feed on higher plants and their byproducts. There are several that feed on paper products, paste, fabrics, and books. This household pest is rarely found in the garden but is frequently found in damp areas within the home.<\/p>\n\n\n\n<p><strong><em>Orthoptera<\/em><\/strong>. Orthoptera includes grasshoppers (Figure 15), crickets, camel crickets, and cockroaches. Adult orthopterans are medium to large sized and often rather hard-bodied insects that go through simple metamorphosis\u2014that is, where the immature nymphs resemble adults except for having underdeveloped wings. Insects in this order possess chewing mouthparts. Thus, both nymphs and adults can be damaging to plants. Adults usually have two pairs of wings, although in some species they are either absent or rudimentary. The forewings are elongate, narrow, and hardened; the hind wings are membranous and fan-like (grasshoppers and allies). The hind legs of many orthopterans are enlarged for jumping. Cerci, appendages at the end of the abdomen, are usually present. Most orthopterans are plant feeders and can be very destructive. Cockroaches are sometimes grouped in an order of their own called Blattodea. Cockroaches are primarily household scavengers and not garden <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#h\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#h\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>herbivores<\/strong> (opens in new window)<\/a>.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-16-2.jpg\" alt=\"Close-up of European earwig. Two prominent cerci look like jagged, sharp horns protruding at the end of its abdomen.\" class=\"wp-image-3258\" width=\"300\" height=\"450\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-16-2.jpg 400w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-16-2-200x300.jpg 200w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><figcaption class=\"wp-element-caption\">Figure 16. European earwigs, Forficula auricularia, belong to the insect order Dermaptera. Earwigs have prominent cerci at the end of their abdomen. Photo by M. Asche.<\/figcaption><\/figure><\/div>\n\n\n<p><strong><em>Dermaptera<\/em><\/strong>. Dermaptera are the earwigs (Figure 16). Adults are moderate-sized insects, and most are active at night. They go through simple metamorphosis and have chewing mouthparts and long antennae. Earwigs have short, hardened outer wings that cover the folded membranous nner wings and prominent forceps (cerci) at the end of their abdomen. The pincer-like cerci are used for defensive posturing, courtship, and manipulating the wings. Some species have glands on the dorsal part of the abdomen that can emit a foul-smelling chemical that serves as protection. They are mainly scavengers but can be herbivorous or predaceous on soft-bodied insect pests.<\/p>\n\n\n\n<p><strong><em>Isoptera<\/em><\/strong>. Termites are in the order Isoptera (Figure 17). Termites are small- to medium-sized insects that are sometimes confused with ants. Termites always have straight antennae, whereas ants have elbowed antennae. Termites have a broad waist, which makes it difficult to differentiate between the thorax and the abdomen, while ants tend to have a thin waist. Another distinction is that reproductive termite adults have two pairs of equal-sized wings; while ants in their reproductive stage have two pair of wings of unequal size and length (forewings are longer than the hindwings). Termites go through simple metamorphosis and live in a variety of wood habitats. Some live in moist subterranean conditions, while others live in dry conditions aboveground. They live in social groups and have a highly developed caste system. Termites have chewing mouthparts and can digest cellulose with the assistance of microbes in their digestive tract. Termites are typically not a garden pest.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-spacing-before--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-17_Left-1.jpg\" alt=\"White termites pack a wooden gallery they\u2019ve carved. \" class=\"wp-image-3260\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-17_Left-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-17_Left-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 17. Western subterranean termite, Reticulitermes hesperus, workers (left photo) and termite reproductive adults (right photo). Photos by M. Asche (left photo) and M. Bush (right photo).<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-17_Right-1.jpg\" alt=\"Four winged termite adults next to a tape measure showing their average length to be around seven or eight millimeters.\" class=\"wp-image-3259\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-17_Right-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-17_Right-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-18-3.jpg\" alt=\"European praying mantis on underside of grass stalk.\" class=\"wp-image-3263\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-18-3.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-18-3-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 18. Adult European praying mantis, Mantis religiosa. Photo by M. Asche.<\/figcaption><\/figure><\/div>\n\n\n<p><strong><em>Mantodea<\/em><\/strong>. One other order that gardeners should be aware of is the praying mantids (Mantodea; Figure 18). Praying mantids go through simple metamorphosis, and both the nymphs and the adults specialize in hunting and feeding on garden pests like grasshoppers, flying insects, and the larger insect pests found in the garden or home landscape. Praying mantids are generalist predators and will eat anything that they can catch, including beneficial insects and pollinators.<\/p>\n\n\n\n<p class=\"wsu-spacing-after--large\"><strong><em>Hemiptera<\/em><\/strong>. The order Hemiptera includes the true bugs (Figure 19), aphids (Figure 20), scales, leafhoppers, cicadas, and whiteflies. Hemipterans go through simple metamorphosis and have piercing-sucking mouthparts. True bugs (suborder Heteroptera) differ from aphids and other hemipterans by having two pairs of wings as adults which lay flat on their body. The forewings of true bugs have a basal portion that is thickened and leathery while the distal portion is membranous as are the hindwings. Aphids and other hemipterans (suborder Homoptera) have two pairs of membranous wings which are held rooflike over their adult bodies. True bugs may be plant feeders or predators, while many of the other hemipterans, including aphids, scale insects, leafhoppers, and whiteflies, use their piercing-sucking mouthparts to pierce, then suck fluids from their plant host. Often these pests can be identified by the copious amounts of sticky fluid, called <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#h\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#h\" target=\"_blank\"><strong>honeydew<\/strong> (opens in new window)<\/a>, that they excrete after feeding. Many aphid species go through complicated life cycles that include <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\"><strong>parthenogenesis<\/strong> (opens in new window)<\/a> (asexual reproduction) and <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#a\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#a\" target=\"_blank\"><strong>alternate hosts<\/strong> (opens in new window)<\/a>. Several species in this order can carry plant pathogens from one plant to another on or in their piercing-sucking mouthparts, further contributing to their pest status in home gardens.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-19_Left-1.jpg\" alt=\"Close-up of brown marmorated stink bug.\" class=\"wp-image-3264\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-19_Left-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-19_Left-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 19. The brown marmorated stink bug, <em>Halyomorpha halys<\/em> (left), and western box elder bug, <em>Boisea rubrolineata<\/em> (right), are members of the order Hemiptera (<em>suborder Heteroptera<\/em>). Note the forewings of these true bugs. Photos by T. Murray (left) and M. Asche (right).<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-19_Right-1.jpg\" alt=\"Close-up of western boxelder bug.\" class=\"wp-image-3265\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-19_Right-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-19_Right-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n\n<p><strong><em>Thysanoptera<\/em><\/strong>. Thrips are in the order Thysanoptera (Figure 21). Thrips are very small, slender-bodied insects which may be wingless or possess two pairs of wings. The wings are unique in the insect world in that they are long and narrow with few or no veins and fringed with long hairs. The wing appearance is reminiscent of bird feathers. The metamorphosis of thrips is intermediate between simple and complex. Mouthparts of thrips are of the sucking type (sometimes also described as rasping-sucking mouthparts). Many thrips species are herbivorous and damage plant tissues by puncturing plant cell walls and sucking out the cellular contents. Damage is usually minimal and limited to surface cells but can lead to loss of color in flowers and leaves or russeting of fruit and vegetable surfaces. Thrips are known to transmit several plant diseases. A few thrips species are predacious and a few are fungal feeders.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-spacing-before--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-20_Left-1.jpg\" alt=\"Green aphids on a green leaf.\" class=\"wp-image-3266\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-20_Left-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-20_Left-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 20. Aphids (left photo) and whiteflies (right photo) are members of Hemiptera (<em>suborder Homoptera<\/em>) as well. Note the piercing-sucking mouthparts and the wings on the whitefly. Photos by M. Asche (left photo) and M. Bush (right photo).<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-20_Right-1.jpg\" alt=\"Close-up of white fly.\" class=\"wp-image-3267\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-20_Right-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-20_Right-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-21-1.jpg\" alt=\"Close-up of adult and juvenile onion thrips.\" class=\"wp-image-3268\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-21-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-21-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 21. Adult and immature onion thrips, Thrips tabaci. Photo by M. Asche.<\/figcaption><\/figure><\/div>\n\n\n<p><strong><em>Coleoptera<\/em><\/strong>. The Coleoptera order has more species than any other insect order and include the beetles (Figure 22) and weevils (Figure 23). Beetles are variable in size, and some of the largest and the smallest insects on the planet belong to this order. Coleoptera go through complex metamorphosis, so the immature larvae do not resemble the adults and may occupy totally different environments. Most beetles have chewing mouthparts. Adult weevils possess a snout, at the end of which are the chewing mouthparts. The larvae of most beetles have a head capsule and three pairs of legs on the thorax; weevil larvae lack legs on the thorax. Adult beetles usually have noticeable antennae. Most adults have two pairs of wings.<\/p>\n\n\n\n<p class=\"wsu-spacing-after--large\">The outer pair of wings (<a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#e\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#e\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>elytra<\/strong> (opens in new window)<\/a>) are hardened, while the inner or hindwings are membranous. A few species are practically wingless and some may have only an outer pair of wings. Beetles live in a variety of habitats (aquatic, terrestrial, and subterranean) and have diverse feeding habits and food sources, including plants, dung, and carrion. Many beetle species are predators of other arthropods as larvae or as adults. Predaceous beetles are beneficial insects that should be conserved in home gardens.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-22-1.jpg\" alt=\"Predaceous ground beetle on moss.\" class=\"wp-image-3269\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-22-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-22-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 22. The Coleoptera order includes beetles. This predaceous ground beetle (family: Carabidae) has wicked-looking mandibles used for capturing prey. Photo M. Peterson.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-23-1.jpg\" alt=\"A weevil with a long snout perched on a flower.\" class=\"wp-image-3270\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-23-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-23-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n\n<p><em><strong>Neuroptera<\/strong><\/em>. Neuroptera is one order of insects that home gardeners will want to recognize, not because they are garden pests but because they are key insect predators (Figure 24). Adult neuropterans include lacewings, snakeflies, and mantidflies, and they are characterized by having soft bodies and four membranous wings with multiple nerve-like veins. All members of this insect order undergo complex metamorphosis. Often the larvae are highly mobile and flattened, with an alligator-like appearance that helps them specialize in feeding on soft-bodied insects. Green and brown lacewing larvae feed primarily on aphids, other small insects, and are commonly known as aphidlions.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-spacing-before--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-24_Left-1.jpg\" alt=\"Green lacewing on a plant stem, showing its slender green body, long antennae, golden eyes, and clear veined wings folded over its back.\" class=\"wp-image-3271\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-24_Left-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-24_Left-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 24. Green lacewing larva (left photo), and adult lacewing (right photo) (order: Neuroptera). Photos by D. James (top) and M. Asche (bottom).<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-24_Right-2.jpg\" alt=\"Lacewing larva with thick midsection, segments, and two large, front mandibles.\" class=\"wp-image-3272\" width=\"454\" height=\"531\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-24_Right-2.jpg 400w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-24_Right-2-256x300.jpg 256w\" sizes=\"(max-width: 454px) 100vw, 454px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n\n<p><strong><em>Hymenoptera<\/em><\/strong>. Hymenoptera includes bees (Figure 25), ants, wasps (Figure 26), and sawflies. Hymenopterans go through complex metamorphosis.<\/p>\n\n\n\n<p>In general, they have chewing mouthparts, while some groups, such as the honey bee (<em>Apis mellifera<\/em>), have chewing-lapping mouthparts to reach and gather flower nectar.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-spacing-before--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-25-1.jpg\" alt=\"Close-up of honey bee on flower.\" class=\"wp-image-3273\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-25-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-25-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 25. The honey bee, Apis mellifera, is a member of the Hymenoptera family and one of the most important pollinators of flowers in home gardens. Photo by M. Peterson.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-26-1.jpg\" alt=\"Close-up of yellowjacket on flower.\" class=\"wp-image-3274\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-26-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-26-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 26. Yellowjackets (family: Vespidae) are in the insect order Hymenoptera and have a nasty reputation for stinging and defending their nest from intruders. Photo by M. Peterson.<\/figcaption><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n\n<p>Adults have antennae that are long with generally ten or more segments. Adult hymenopterans have two pairs of membranous wings. They are found in many habitats and on many flowers or vegetation types. Many have parasitic or predacious lifestyles and are considered natural enemies of garden pests. Others can induce galls within which they feed (Figure 12, bottom photo). Many bee, wasp, and ant larvae have no legs. Some sawfly larvae have true jointed legs on the thorax and fleshy <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>prolegs<\/strong> (opens in new window)<\/a> (without gripping hooks, called \u201ccrochets\u201d) on the abdomen. Many hymenopterans construct nests and are highly social with a complex caste system. Some species have modified their egg-laying structures into specialized stingers to inject defensive venoms, such as honey bees and yellowjacket wasps. While these stinging tendencies cause gardeners to label them as pests, yellowjackets are voracious predators of insect pests in the garden. Bees, including honey bees, are some of the most important flower pollinators and thus are key to producing most garden fruits and vegetables.<\/p>\n\n\n\n<p class=\"wsu-spacing-after--large\"><strong><em>Lepidoptera<\/em><\/strong>. The order Lepidoptera includes moths (Figure 27) and butterflies (Figure 28). Moths and butterflies vary in size from very small to large insects. One species of moth, <em>Thysania agrippina<\/em>, has the largest wingspan of any known insect, almost twelve inches! Lepidoptera go through complex metamorphosis. The larvae of this order have chewing mouthparts while the adults have a coiled tube for sucking nectar and other liquids. Larvae (commonly known as caterpillars) are unique in that they have prolegs armed with gripping hooks (better for holding onto plants) on their abdomen. These hooks are called \u201ccrochets.\u201d Moth and butterfly larvae are key pests that specialize in using their chewing mouthparts to feed on plant tissues. Adults have two pairs of well-developed wings that are covered with small scales. The antennae of moths are variable, ranging from long and slender threads to something resembling a feather. Butterflies have a single type of antenna which can be described as a filament terminating in a knob. While caterpillars are viewed as key pests of plants, many adult butterflies and moths use their <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>proboscis<\/strong> (opens in new window)<\/a> or elongated mouthparts to siphon liquids (primarily nectar) from plants and are viewed as important pollinators as well as esthetically pleasing visitors to home gardens. Adults that do feed, feed only on liquids (primarily nectar).<\/p>\n\n\n<div class=\"wsu-row wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-27_Left-2.jpg\" alt=\"Tomato hornworm larva on twig.\" class=\"wp-image-3592\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-27_Left-2.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-27_Left-2-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 27. Tomato hornworm larva, <em>Manduca quinquemaculata<\/em> (left), and adult white-lined sphinx moth, <em>Hyles lineata<\/em> (right). Photos by M. Peterson.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-27_Right-1.jpg\" alt=\"Top-down view of adult white-lined sphinx moth on bark of tree.\" class=\"wp-image-3593\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-27_Right-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-27_Right-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-28_Left.jpg\" alt=\"West coast lady butterfly on dewy leaves, showing orange, black and white coloration on wings.\" class=\"wp-image-3595\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-28_Left.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-28_Left-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 28. West coast lady butterfly, <em>Vanessa annabella<\/em> (left), and western tiger swallowtail, <em>Papilio rutulus<\/em> (right). Photos by M. Peterson.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-28_Right-1.jpg\" alt=\"Side view of western tiger swallowtail, showing vibrant orange, black, yellow, and blue coloration.\" class=\"wp-image-3596\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-28_Right-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-28_Right-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-29-1.jpg\" alt=\"Side view of cat flea, showing hairless, shiny body long legs, relative to body size.\" class=\"wp-image-3597\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-29-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-29-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 29. The cat flea, <em>Ctenocephalides felis<\/em>. Photo by M. Peterson.<\/figcaption><\/figure><\/div>\n\n\n<p><strong><em>Siphonaptera<\/em><\/strong>. Fleas are in the order Siphonaptera (Figure 29). Fleas are small insects with laterally compressed bodies that allow them to move easily through hair and fur. They undergo complex metamorphosis. They have piercing-sucking mouthparts as adults and chewing mouthparts as larvae. Their antennae are quite short and fit into a groove on the head. They do not possess wings but have powerful legs for jumping. Fleas are <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>parasites<\/strong> (opens in new window)<\/a> as adults, feeding on the blood of birds and mammals. Some transmit disease (e.g., plague) or parasitic organisms (e.g., dog tapeworm). The larvae feed on organic debris, particularly adult flea feces. Flea larvae are whitish, slender, legless, and with a well-developed head. While fleas are not typically found in home gardens, they are pests of humans and pets.<\/p>\n\n\n\n<p><strong><em>Diptera<\/em><\/strong>. Insects in the order Diptera (Figure 30) include mosquitoes, gnats, midges, crane flies, and other flies. Most dipterans are small, hairy, soft-bodied insects. Some are quite minute. They undergo complex metamorphosis. Adults have sponging (like the housefly) or piercing-sucking (like the mosquito) mouthparts. Larvae may have mouth hooks or chewing mouthparts. Adult antennae are variable in length and shape. They have a single pair of membranous forewings. The hindwings are reduced to small, knobbed structures called <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#h\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#h\" target=\"_blank\"><strong>halteres<\/strong> (opens in new window)<\/a> that act as gyroscopes or balancing organs during flight. A few fly species are wingless. Some flies transmit disease between plants or between animals. Larvae of houseflies have no head capsule, while mosquito larvae have a head capsule. Fly habitats are diverse, ranging from aquatic to terrestrial. Their feeding habits are equally diverse, from plant and animal feeders, dung and carrion feeders, to parasites and blood feeders. Some adults are known to pollinate flowers, while other adults (and some larvae) feed as insect predators. Fly larvae can be found in moist garden soils and compost piles where they help decompose organic matter. Other fly larvae, or maggots, can be found in the moist tissues of fruits, vegetables, and plant roots where they are garden pests.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-spacing-before--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-30_Right-2.jpg\" alt=\"Close-up of crane fly. Prominent wings and halteres are visible.\" class=\"wp-image-3599\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-30_Right-2.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-30_Right-2-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 30. Representatives of the Diptera order\u2014crane flies (left photo) and mosquito (right photo). Notice the pair of wings and halteres on the crane fly on the right. Photos by M. Asche.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-30_Left-2.jpg\" alt=\"Close-up of mosquito on yellow flower.\" class=\"wp-image-3598\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-30_Left-2.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-30_Left-2-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n\n<p><strong><em>Other Orders<\/em><\/strong>. Several other insect orders are of little concern to gardeners because they do not cause a lot of plant problems. Some of the more common ones that gardeners may see are stoneflies (Plecoptera), caddisflies (Trichoptera), dragonflies and damselflies (Odonata), and mayflies (Ephemeroptera). The larvae of these orders are all associated with aquatic habitats. Many of these insects do not feed as adults, but dragonflies are daytime flying predators that use their legs to capture other flying insects.<\/p>\n\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch15-insect-diversity\">Insect Diversity and Natural History<\/h2>\n\n\n\n<p>The class Insecta is probably the most diverse animal class on the planet. The number of species of insects described so far is close to one million. <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#s\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Systematists<\/strong> (opens in new window)<\/a> (scientists that study evolution and taxonomy) say that if they had access to all microhabitats from which to collect and catalogue insects, there would be many millions more insects known to science. Estimates of the actual number of insect species on earth range from 2 million to 30 million. The most remarkable thing about these numbers is that most Insecta are beneficial in some manner, with less than 1% of the one million known insect species obtaining pest status.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-31-2.jpg\" alt=\"Close-up of braconid wasp next to similarly small aphids.\" class=\"wp-image-3600\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-31-2.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-31-2-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 31. A tiny (2 mm long) braconid wasp prepares to lay an egg inside a host aphid. Photo by M. Bush.<\/figcaption><\/figure><\/div>\n\n\n<p>While animal, plant, and some structural pests are arguably a constant threat, many so-called \u201cpests\u201d are, in a natural setting, quite beneficial. For example, carpenter ants and termites can be pests to humans, but in nature they are beneficial as recyclers of rotting wood. Even the lowly housefly (<em>Musca domestica<\/em>), detested by everyone, is extremely important to the health of the earth, because housefly maggots are pioneer organisms rendering rotting vegetation, dung, and carrion down to the next recyclable level.<\/p>\n\n\n\n<p>Insects inhabit nearly all habitats and microhabitats and function in a vast number of <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#n\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#n\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>niches<\/strong> (opens in new window)<\/a>. <em>Microhabitats<\/em>, for the purposes of this chapter, is defined as where these animals live, while \u201cniche\u201d will be used to connote the job or role an insect performs in its living space or microhabitat. The open seas and oceans are among the few habitats where insects are not found; however, salt lakes, along seashores, in backwaters, and in estuaries associated with oceans are home to many insect species.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-32-1.jpg\" alt=\"Close-up of paperwasp feeding on a green insect.\" class=\"wp-image-3601\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-32-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-32-1-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 32. A paperwasp, <em>Polistes dominula<\/em>, feeding on an insect prey item. Photo by A.J. Hersh.<\/figcaption><\/figure><\/div>\n\n\n<p>If you looked at the types of microhabitat or niche categories of insects you would find that they resemble those of many animal groups, in terms of lifestyles and food patterns. Decomposers, such as termites, exemplify one such lifestyle in that they live in their food (rotting logs). Another common category would include predators, such as dragonflies and many others, that make their living by catching and feeding on other animals. Some insects are parasites. Parasites live in or on another host organism and derive nutrients at the other\u2019s expense. Parasites generally do not kill their host. Insects also have a niche that resembles both parasite and predator, called <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>parasitoid<\/strong> (opens in new window)<\/a>. Parasitoids lay eggs near, on, or inside the intended prey (Figure 31) so that when eggs hatch, the larva immediately burrows into the host and slowly consumes it until the host dies. The difference between parasitoids and predators is that predators immediately kill their prey (Figure 32).<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-33-1.jpg\" alt=\"Honey bee on pinkish-white flower.\" class=\"wp-image-3603\" width=\"300\" height=\"450\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-33-1.jpg 400w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-33-1-200x300.jpg 200w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><figcaption class=\"wp-element-caption\">Figure 33. Honey bee, <em>Apis mellifera<\/em> (Order: Hymenoptera, Family: Apidae). Photo by M. Asche.<\/figcaption><\/figure><\/div>\n\n\n<p>Herbivores in all types of habitats dominate the insect world. Aphids, caterpillars, and grasshoppers are just a few examples of this niche, and, as one might expect, many are very important economically. Pollinators like bees (Figure 33) are a variation of the herbivore niche and are of key importance to many plant organisms on the planet.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><em>Host Relationships<\/em><\/h3>\n\n\n\n<p>When studying insects, it becomes quite clear that they have a range of dependency on their targeted foods or hosts. In the case of herbivore insects, some have an extremely limited host relationship that includes a single plant species. A local example includes the spiny rose gall wasp which makes its living on wild rose and nothing else. Some herbivores have only a few hosts that may or may not be related. The cottony camellia scale is one of these and for the most part is only found on camellia, holly, euonymus, and yew. There are, of course, many generalists among plant-feeding insects, and they may be found on dozens of plant species. A good example of a generalist is the brown marmorated stink bug (Figure 19, top photo) that can feed on over 300 different species of plants. Predators and parasitoids may exhibit a range of diversity in their feeding habits. Predators are usually generalists, feeding on whatever they can find and overpower\u2014for example, predacious ground beetles that feed on cutworms and crane flies, among others, in yards and gardens. Parasitoids tend to be specific to certain species or species groups. For example, some parasitoid ichneumonid wasps lay their eggs only on bark beetle larvae, while the parasitoid wasp <em>Trissolcus japonicus<\/em> prefers to lay its eggs only in the eggs of the brown marmorated stink bug.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-34-1.jpg\" alt=\"Line graph showing population size over time in relation to environmental carrying capacity. Y-axis (vertical): Population size. X-axis (horizontal): Time. A horizontal line labeled Equilibrium crosses the middle of the graph. A higher horizontal line near the top is labeled Environmental Carrying Capacity, K. The population curve fluctuates above and below equilibrium, with labeled peaks and troughs: Peaks above equilibrium: B1, B2, A1, B3, B4. Deep low point below equilibrium: C1. After C1, the curve rises sharply, approaches the carrying capacity, and then dips slightly. The figure illustrates how populations oscillate around equilibrium and carrying capacity over time, demonstrating overshoots, declines, and cycles of recovery.\" class=\"wp-image-3604\" width=\"550\" height=\"366\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-34-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-34-1-300x200.jpg 300w\" sizes=\"(max-width: 550px) 100vw, 550px\" \/><figcaption class=\"wp-element-caption\">Figure 34. Graph of variations in population density for an animal species over time. Image: WSU.<\/figcaption><\/figure><\/div>\n\n\n<h3 class=\"wp-block-heading\"><em>Life Cycles<\/em><\/h3>\n\n\n\n<p>Insects, like all other animals and plants, have life cycles as individuals and as populations. It is important to know these life cycles if you are trying to make decisions about managing insects.<\/p>\n\n\n\n<p><em><strong>Population Cycles<\/strong><\/em>. The number of animals in a local population varies from year to year and even within a single year, for a variety of reasons. Figure 34 illustrates the sort of population size changes that can occur because of various environmental or climatic events. The gentle dips and rises (B1, B2, B3) are driven by density-dependent <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#b\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#b\" target=\"_blank\"><strong>biotic<\/strong> (opens in new window)<\/a> factors, such as predators, disease, and food quality or quantity. These cycles fluctuate with weather and interactions with other plant and animal populations that keep them near equilibrium with the resources and conditions of the local environment. The rather dramatic crash and upward surge shown in the middle of the graph of Figure 34 (A1) reflects the effect of a density-independent, or <a rel=\"noreferrer noopener\" href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#a\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#a\" target=\"_blank\"><strong>abiotic<\/strong> (opens in new window)<\/a>, factor, which could be any catastrophic event or even aberrant climate. The crash of a population of insects may reflect, for instance, a late spring frost that kills overwintered insects that have just emerged and begun feeding and were not protected from the sudden cold. An even more dramatic depression of populations would occur in the event of something like a volcanic eruption. Another catastrophic event (C1) might result in a population fall, followed by a population build-up of dramatic proportion that would look like the rise shown in the far right of the graph of Figure 34. This might be the result of a dynamic die-off of natural enemies (such as from application of a broad-spectrum insecticide) that leads to a population explosion that quickly reaches the environmental <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>carrying capacity<\/strong> (opens in new window)<\/a> (total population of a species that can be supported by the local environment), at which point members of the population eat themselves out of house and home or experience a plague-like disease so that the population crashes.<\/p>\n\n\n\n<p><strong><em>Individual Life Cycles<\/em><\/strong>. One might ask, What is the usual longevity of insects, or How long do they live? This can only be answered by looking at each species or species group individually. For example, many cutworms have a one-year life cycle. Some species, like houseflies, under optimal conditions may live only a couple of weeks or even just five days from egg hatch to adulthood. Then again, some beetles, like the golden buprestid beetle (<em>Buprestis aurulenta<\/em>), have been documented as persisting as larvae in structural wood framing for up to 25 years.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><em>The Insect Success Story<\/em><\/h3>\n\n\n\n<p class=\"wsu-spacing-after--default\">Insects have been on Earth since the Devonian Period (about 400 million years), which is a testament to their success as a class of animals. There is much that contributes to this notable persistence and success, such as insect size, reproductive rate, structure, their physical ability to respond to change quickly, and their adaptability. Their success can largely be attributed to their ability to adapt. There are so many unique adaptations but only a few of the more dramatic ones will be addressed.<\/p>\n\n\n\n<p>In the PNW\u2014a temperate region\u2014there is a wide variation in temperatures, especially in the winter. Insects are very susceptible to the drying, freezing winds of winter because of their surface area-to-volume ratio\u2014they cannot afford to lose any moisture. Insects would freeze very rapidly if they were not equipped with behavioral and physiological strategies for survival. Insects will seek out protective hiding places in soil, tree bark, crevices, under rocks, and other places to avoid cold temperatures. Persistent snow can provide them with a protective thermal blanket. To avoid freezing, many species, prompted by consistent lower daily temperatures and the shortening of day lengths, produce glycerol in their blood. Glycerol is an antifreeze that prevents ice crystals from forming in blood and cells. (Insects \u201cinvented\u201d antifreeze, not humans!) With these physiological and behavioral adaptations, insects of the PNW region have successfully warded off one of their greatest foes\u2014freezing winters.<\/p>\n\n\n\n<p>Insects are masters at reproduction. Insects, especially the ones usually considered pests, can have a high rate of reproduction. Houseflies, <em>Musca domestica<\/em>, can commonly lay 300\u2013400 eggs in a lifetime. The Australian rain moth, <em>Trictena atripalpis<\/em>, has the highest record for a nonsocial insect, with a single female laying over 40,000 eggs. Queens of social insects are egg-laying machines. The African driver ant, <em>Dorylus wilverthi<\/em>, can lay up to 4 million eggs every 25 days. Some insects can reproduce without mating through parthenogenesis or asexual reproduction from unfertilized eggs. Some of our pestiferous aphid species can rapidly develop large populations by asexual reproduction. This competitive method allows for aphids to find and colonize plants quickly.<\/p>\n\n\n\n<p>Humans have used insect behaviors and their many adaptations against them in integrated pest management strategies. For example, several insects (such as aphids) overwinter in the egg stage on primary hosts. If a pest does this behavior, it could be a candidate for control with dormant oil applications in the spring before the buds open. The larvae of the cherry bark tortrix (CBT) moth (<em>Enarmonia formosana<\/em>) construct a \u201cfrass tube,\u201d a silken cell with fecal pellets at the entrance of their gallery carved underneath the bark of cherry trees. The flight period for the adult moth lasts from April until September, which means that all life stages are present in the cherry orchard throughout the growing season. However, in October, CBT larvae are actively building their frass tubes. This is a great opportunity for a well-timed insecticide. A small amount of insecticide applied to the frass tubes in October can eliminate an infestation of CBT.<\/p>\n\n\n\n<p>Another management example is the use of <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#p\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>pheromones<\/strong> (opens in new window)<\/a>. Many moths are nocturnal and hide by day. Thus, with moths, it makes sense to communicate chemically rather than visually, and many insects do so by emitting \u201cexternal hormones\u201d called pheromones. Sex pheromones are used by female moths to attract mates. Scientists often re-create the sex pheromone, place the pheromone in a dispenser, and hang the dispenser in a sticky trap wherein male moths attracted to the pheromone become stuck in the trap (a strategy called attract-and-kill). Alternatively, pest managers use pheromone traps to determine the presence of a pest and to quantify how numerous they are. This allows managers to accurately time insecticide applications to target the most vulnerable life stage of the pest. Another type of pheromone includes trail pheromones emitted by ants to assist in finding food and returning to the nest. Alarm pheromones that call nest mates to help defend the hive are used by many stinging hymenopterans, such as the honey bee and most yellowjacket species, among others.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-after--large wsu-spacing-before--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-35_Left-1.jpg\" alt=\"A white spider blending in among white flowers.\" class=\"wp-image-3606\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-35_Left-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-35_Left-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 35. Cryptic coloration by crab spiders. Photos by M. Asche.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-35_Right-1.jpg\" alt=\"A yellow spider\u2019s coloration nearly perfectly matches the coloration of the surrounding flowers.\" class=\"wp-image-3607\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-35_Right-1.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-35_Right-1-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-36-5.jpg\" alt=\"Side view of butterfly with coloration that is nearly indistinguishable from that of a dead leaf or bark.\" class=\"wp-image-3612\" width=\"400\" height=\"400\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-36-5.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-36-5-300x300.jpg 300w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-36-5-150x150.jpg 150w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><figcaption class=\"wp-element-caption\">Figure 36. A butterfly\u2019s detection among dead leaves may be difficult due to its coloration when its wings are folded at rest. Photo by D. James.<\/figcaption><\/figure><\/div>\n\n\n<h3 class=\"wp-block-heading\"><em>Social Organization<\/em><\/h3>\n\n\n\n<p>There are several insects from different orders that show some level of social organization. Some of the more advanced of these social insects include termites, bees, ants, and stinging wasps. Pest management strategies can sometimes take advantage of this social behavior. For example, toxic baits that ant and yellowjacket workers find are then brought back to the nest to feed larvae and the queen. Conversely, the consequences of disturbing social insects, like throwing rocks at yellowjackets nests or kicking thatching ant mounds, can have an unsafe outcome. Due to the beneficial role of these social insects as predators, avoid approaching or disturbing the nest or mound altogether.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><em>Cryptic Coloration and Mimicry<\/em><\/h3>\n\n\n\n<p>In addition to social organization, the world of insects holds another set of bizarre adaptations that are simply amazing. One type of adaptation that provides insects with a measure of safety but can frustrate home gardeners trying to find or identify pests is called deceptive or cryptic coloration. There are several types of <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>cryptic coloration<\/strong> (opens in new window)<\/a> and mimicry. For instance, many insect species resemble rocks, twigs (Figure 35), brambles, dead leaves (Figure 36), or living leaves, which allows the insects to hide in plain sight. This is known as cryptic coloration. Cryptic mimicry provides these insects with some form of camouflage to avoid detection or to help predators ambush their prey.<\/p>\n\n\n<div class=\"wsu-row wsu-spacing-before--xxmedium wsu-spacing-after--large wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-37-6.jpg\" alt=\"Top-down view of a monarch butterfly on a cluster of red flowers.\" class=\"wp-image-3613\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-37-6.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-37-6-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 37. Monarch butterfly, <em>Danaus plexippus<\/em>. Monarchs are the model insect for viceroy butterflies as an example of Muellerian mimicry. Photo by D. James.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"600\" height=\"400\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-38-4.jpg\" alt=\"Viceroy butterfly against a black background.\" class=\"wp-image-3614\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-38-4.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-38-4-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption class=\"wp-element-caption\">Figure 38. Viceroy butterfly, <em>Limenitis archippus<\/em>. Photo by A. Antonelli.<\/figcaption><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"alignright size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Figure-39-2.jpg\" alt=\"A syrphid fly on a yellow flower.\" class=\"wp-image-3615\" width=\"424\" height=\"282\" \/><figcaption class=\"wp-element-caption\">Figure 39. Despite the warning colors, this syrphid fly (notice the one pair of wings only) is totally harmless. This is an example of Batesian mimicry. Photo by M. Peterson.<\/figcaption><\/figure><\/div>\n\n\n<p>Two other types of mimicry are worthy of mention. One is <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#m\" data-type=\"URL\" data-id=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#m\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Muellarian mimicry<\/strong> (opens in new window)<\/a>, where both the mimic and the model insect are dangerous creatures and their similar appearances give a universal message of warning. Recently, monarch and viceroy butterflies (Figure 37 and Figure 38) were recharacterized to Muellarian mimicry because it was found that viceroy butterflies were also found to be distasteful to predatory birds. This is still under some debate.<\/p>\n\n\n\n<p>The other type of mimicry is Batesian mimicry where the model has a defensive adaptation, but the mimic does not. A commonly seen example is that of adult syrphid flies that mimic the yellow and black coloration of stinging insects like yellowjacket wasps (Figure 39).<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch15-further-reading\">Further Reading<\/h2>\n\n\n\n<p>Antonelli, A.L., T.L. Whitworth, C.R. Foss, C.A. Ramsay, and D.A. Suomi. 2006. Pest Management Study Manual for Pest Management Professionals. <em>Washington State University Extension Publication<\/em> MISC 0096. Washington State University.<\/p>\n\n\n\n<p>Arnett, R.H. Jr. 1985. <em>American Insects\u2014A Handbook of the Insects of America North of Mexico<\/em>. New York: Van Nostrand Reinhold Company.<\/p>\n\n\n\n<p>Berenbaum, M.R. 1996. <em>Bugs in the System: Insects and Their Impact on Human Affairs<\/em>. New York: Perseus Books.<\/p>\n\n\n\n<p>Cranshaw, W. 2004. <em>Garden Insects of North America: The Ultimate Guide to Backyard Bugs<\/em>. Princeton, NJ: Princeton University Press.<\/p>\n\n\n\n<p>Elzinga, R.J. 1978. <em>Fundamentals of Entomology<\/em>. Englewood Cliffs, NJ: Prentice Hall, Inc.<\/p>\n\n\n\n<p>Olkowski, W., S. Daar, and H. Olkowski. 1991. <em>Common Sense Pest Control<\/em>. Newtown, CT: Taunton Press.<\/p>\n\n\n\n<p>Peterson, M.A. 2018. Pacific Northwest Insects. Seattle Audubon Society.<\/p>\n\n\n\n<p>Ross, H.H., C.A. Ross, and J.R.P. Ross. 1982. <em>A Textbook of Entomology<\/em>, 4th edition. New York: John Wiley &amp; Sons.<\/p>\n\n\n\n<p>Schauff, M.E. 2007. <a href=\"http:\/\/www.ars.usda.gov\/SP2UserFiles\/ad_hoc\/12754100CollectingandPreservingInsectsandMites\/collpres.pdf\" target=\"_blank\" rel=\"noreferrer noopener\">Collecting and Preserving Insects and Mites: Techniques and Tools (link to PDF document)<\/a>. Edited from USDA Misc. Publication no. 1443, published by the Agricultural Research service in 1986 and edited by G.C. Steyskal, W.L. Murphy, and E.M. Hoover.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Insect Keys, Illustrative Works, Taxonomic Texts, and <br>Entomological Databases\/Collections<\/h3>\n\n\n\n<p>Arnett, R.H., Jr., and R.L. Jacques, Jr. 1981. <em>Simon and Schuster\u2019s Guide to Insects<\/em>. Simon and Schuster: New York.<\/p>\n\n\n\n<p>Bland, R.G., and H.E. Jacques. 1978. <em>How to Know the Insects<\/em>, 3rd edition. Dubuque, IA: Wm. C. Brown Co. Publishers.<\/p>\n\n\n\n<p>Borror, D.G., and R.E. White. 1970. <em>A Field Guide to the Insects of America North of Mexico<\/em>. Boston: Houghton Mifflin Co.<\/p>\n\n\n\n<p>BugGuide. 2024. <a href=\"http:\/\/bugguide.net\/node\/view\/15740\" target=\"_blank\" rel=\"noreferrer noopener\">Identification, Images, and Information for Insects, Spiders, and Their Kin for the United States and Canada (opens in new window)<\/a>.<\/p>\n\n\n\n<p>Chu, H.F. 1949. <em>How to Know the Immature Insects<\/em>. Boston: Wm. C. Brown Co.<\/p>\n\n\n\n<p><a href=\"https:\/\/museum.entomology.wsu.edu\/\" target=\"_blank\" rel=\"noreferrer noopener\">James Entomological Collection (opens in new window)<\/a>. Washington State University, Pullman.<\/p>\n\n\n\n<p>Marshall, S.A. 2006. <em>Insects: Their Natural History and Diversity<\/em>. Buffalo, NY: Firefly Books Inc.<\/p>\n\n\n\n<p>Milne, L., and M. Milne. 1997. <em>The Audubon Society Field Guide to North American Insects and Spiders<\/em>, 16th printing. New York: Alfred A. Knopf.<\/p>\n\n\n\n<p>Triplehorn, C.A., and N.F. Johnson. 2005. <em>Introduction to the Study of Insects<\/em>, 7th edition. Belmont, CA: Thomson Brooks\/Cole.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Michael R. Bush, Entomologist, Washington State Department of Agriculture Yakima County Todd A. Murray, Director, Puyallup Research and Extension Center, Washington State University Arthur L. Antonelli, Extension Entomologist Emeritus (deceased), Washington State University Introduction The animal kingdom includes beneficial organisms (opens in new window) and natural enemies (opens in new window) as well as key [&hellip;]<\/p>\n","protected":false},"author":241,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_wsuwp_accessibility_report":null},"categories":[],"tags":[],"_links":{"self":[{"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/pages\/1425"}],"collection":[{"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/users\/241"}],"replies":[{"embeddable":true,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/comments?post=1425"}],"version-history":[{"count":142,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/pages\/1425\/revisions"}],"predecessor-version":[{"id":4567,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/pages\/1425\/revisions\/4567"}],"wp:attachment":[{"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/media?parent=1425"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/categories?post=1425"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/tags?post=1425"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}