{"id":562,"date":"2025-10-29T14:25:25","date_gmt":"2025-10-29T21:25:25","guid":{"rendered":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/?page_id=562"},"modified":"2026-04-06T10:25:11","modified_gmt":"2026-04-06T17:25:11","slug":"chapter-2-plant-nomenclature-and-identification","status":"publish","type":"page","link":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/chapter-2-plant-nomenclature-and-identification\/","title":{"rendered":"Chapter 2: Plant Nomenclature and Identification"},"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\/10\/Pasque-Flower-web-pic.jpg\"\n\t\tsrcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Pasque-Flower-web-pic.jpg 1755w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Pasque-Flower-web-pic.jpg 300w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Pasque-Flower-web-pic.jpg 1024w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Pasque-Flower-web-pic.jpg 768w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Pasque-Flower-web-pic.jpg 1536w\"\n\t\tsizes=\"(max-width: 1755px) 100vw, 1755px\"\n\t\talt=\"Close-up shot of labeled pasque flower bunch (Pulsatilla vulgaris). Vibrant, purple flowers in foreground with blurred buildings in the distance.\"\n\t\tstyle=\"object-position: 82% 95%\"\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\">Plant Nomenclature<br>and Identification<\/h1>\t\t\t\t<div class=\"wsu-hero__caption\">Chapter 2<\/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><strong>Paula Dinius<\/strong>, Urban Horticulturist, Chelan County Extension, 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>Understand the importance of botanical names and the conventions used in naming.<\/li>\n\n\n\n<li>Know botanical terms related to plant morphology that are used in identifying plants.<\/li>\n\n\n\n<li>Understand how to use a dichotomous key to identify plants.<\/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=\"#ch2-introduction\" data-type=\"internal\" data-id=\"#ch2-introduction\">Introduction<\/a><\/li>\n\n\n\n<li><a href=\"#ch2-study-tips\" data-type=\"internal\" data-id=\"#ch2-study-tips\">Study Tips<\/a><\/li>\n\n\n\n<li><a href=\"#ch2-nomenclature\" data-type=\"internal\" data-id=\"#ch2-nomenclature\">Nomenclature<\/a><\/li>\n\n\n\n<li><a href=\"#ch2-scientific-names\" data-type=\"internal\" data-id=\"#ch2-scientific-names\">Scientific Names<\/a><\/li>\n\n\n\n<li><a href=\"#ch2-common-names\" data-type=\"internal\" data-id=\"#ch2-common-names\">Common Names<\/a><\/li>\n\n\n\n<li><a href=\"#ch2-diagnostic-plant-morphology\" data-type=\"internal\" data-id=\"#ch2-diagnostic-plant-morphology\">Diagnostic Plant Morphology<\/a><\/li>\n\n\n\n<li><a href=\"#ch2-identification-keys\" data-type=\"internal\" data-id=\"#ch2-identification-keys\">Identification Keys<\/a><\/li>\n\n\n\n<li><a href=\"#ch2-further-reading\" data-type=\"internal\" data-id=\"#ch2-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=\"ch2-introduction\">Introduction<\/h2>\n\n\n\n<p>The primary purpose of this chapter is to acquaint you with methods of identifying plants and plant materials commonly used for landscape purposes. While most of the principles in plant identification may be botanical in nature, the ultimate objective is to determine the genus and <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> of the plant in question. Once you have identified a plant, then you can determine its characteristics\u2014its cultural requirements, ultimate size, flowering and fruiting requirements, propagation methods, and hardiness. When you know the genus and species of a plant, you can also identify pathological problems and make diagnoses more easily, efficiently, and with more certainty. You will find that many insect and disease problems are fairly host-specific; that is, they will attack only certain species (sometimes only certain individuals within a species), a certain genus, or only a few genera within a family.<\/p>\n\n\n\n<p>There are many complexities in learning how to identify plants\u2014it requires attention to detail. Scientific plant names are not only hard to pronounce but very difficult to spell. Further, the terms used to describe the morphological characteristics of plant parts are part of a whole new language. And the use of plant keys to determine the identity of an unknown plant can at times be frustrating.<\/p>\n\n\n\n<p>In spite of the difficulties, there is a good degree of satisfaction derived from being able to identify plants, especially the less common ones.<\/p>\n\n\n\n<p class=\"wsu-spacing-after--xsmall\">Listed below are some things to know which will greatly help in identifying plants.<\/p>\n\n\n\n<ul>\n<li>Plant names: family, genus, species, <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#v\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>variety<\/strong> (opens in new window)<\/a> or cultivar, common name(s).<\/li>\n\n\n\n<li>Leaves: arrangement, type, shape, margin, color, other distinguishing characteristics.<\/li>\n\n\n\n<li>Buds: location, type, form.<\/li>\n\n\n\n<li>Flowers: type, color, season of bloom.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch2-study-tips\">Study Tips<\/h2>\n\n\n\n<p class=\"wsu-spacing-after--xsmall\">The best methods for studying a subject will vary with the individual. The initial step is to learn the principles involved in plant identification.<\/p>\n\n\n\n<ul>\n<li>Say the genus and species names together many times. Some people benefit by writing the plant names many times together to remember them and get the spelling correct.<\/li>\n\n\n\n<li>Visit internet sites where you can listen to the proper pronunciation of the botanical Latin name. An example is the <a href=\"https:\/\/www.missouribotanicalgarden.org\/plantfinder\/plantfindersearch.aspx\" data-type=\"URL\" data-id=\"https:\/\/www.missouribotanicalgarden.org\/plantfinder\/plantfindersearch.aspx\" target=\"_blank\" rel=\"noreferrer noopener\">Missouri Botanical Garden Plant Finder website (opens in new window)<\/a>.<\/li>\n\n\n\n<li>Spend a little time each day reviewing plant information. The names and characteristics should become more familiar with repetition.<\/li>\n\n\n\n<li>Spend some time just looking at the plants; this makes it a lot easier to identify them.<\/li>\n\n\n\n<li>Try to learn the meaning of the botanical terms; this will make plant identification much easier. For example, <em>macrophyllum<\/em> = large leaf; <em>tomentosum<\/em> = densely woolly; <em>sinensis<\/em> and <em>chinensis<\/em> = from China; and <em>douglasii<\/em> = named for David Douglas.<\/li>\n\n\n\n<li>Visit arboreta, nurseries, garden centers, and local WSU Extension Master Gardener demonstration gardens. Plants in these locations are usually labeled correctly. Get an idea of different growth habits, varieties, and what is available.<\/li>\n\n\n\n<li>Cultivate friends who are knowledgeable on the subject.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch2-nomenclature\">Nomenclature<\/h2>\n\n\n\n<p>Nomenclature is the naming of things. In botany, derivation of plant names is related to taxonomy\u2014each plant\u2019s botanical name includes the name of the genus it belongs to.<\/p>\n\n\n\n<p>The International Code of Nomenclature for Algae, Fungi, and Plants, revised 2018 and listed in the Further Reading section, is published by the <a href=\"https:\/\/www.iapt-taxon.org\/nomen\/main.php\" data-type=\"URL\" data-id=\"https:\/\/www.iapt-taxon.org\/nomen\/main.php\" target=\"_blank\" rel=\"noreferrer noopener\">International Association for Plant Taxonomy (opens in new window)<\/a> and contains the rules and recommendations for official botanical names for plants.<\/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-max-width--xsmall wsu-align-item--center wsu-spacing-after--large wsu-spacing-before--large\" >\r\n        \n\n<p class=\"has-text-align-center wsu-max-width--small wsu-spacing-after--medium wsu-font-size--medium\">Scientific name =<br>botanical name =<br>Latin binomial =<br><em>Genus species<\/em><\/p>\n\n<\/div>\r\n\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch2-scientific-names\">Scientific Names<\/h2>\n\n\n\n<p><em>Genus<\/em>, <em>species<\/em>, and any cultivar or <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>botanical variety <\/strong>(opens in new window)<\/a> name make up the botanical name of a plant. The genus (or generic name) is derived from a Latinized noun and is capitalized. The species name (or specific epithet) is usually a Latin or Greek adjective that describes or further identifies the particular plant of that genus and is not capitalized. A botanical variety, which is also usually a Latinized or Greek descriptive term, may follow the species name and is also not capitalized. All three names are italicized, or if not italicized, they are underlined to denote it as a botanical name.<\/p>\n\n\n\n<p>Use lower case for species and variety.<\/p>\n\n\n\n<p>Examples:<br><em>Kalmia latifolia<\/em> is the species (mountain laurel).<br><em>Kalmia latifolia alba<\/em> is the botanical variety (white flowered mountain laurel).<br><em>Kalmia latifolia<\/em> \u2018Carousel\u2019 is the <a href=\"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/glossary\/#c\" data-type=\"URL\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>cultivated variety<\/strong> (opens in new window)<\/a>, selected through breeding.<br><em>Pseudotsuga menziesii<\/em> is the species (Douglas-fir).<br><em>Pseudotsuga menziesii glauca<\/em> is the botanical variety (blue Douglas-fir).<br><em>Pseudotsuga menziesii <\/em>\u2018Pendula\u2019 is the weeping form of the Douglas-fir.<\/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-max-width--small wsu-align-item--center wsu-spacing-after--large wsu-spacing-before--large\" >\r\n        \n\n<p class=\"has-text-align-center wsu-max-width--small wsu-spacing-after--medium wsu-font-size--medium\">Genus, species, and varietal names <br>must be italicized in writing, or <br>underlined if italics are not possible.<\/p>\n\n<\/div>\r\n\n\n\n<p>Cultivar names are no longer Latinized but are usually in the language of the country of origin. They are not italicized but are set off either by single quotes or preceded by the abbreviation \u201ccv.\u201d<\/p>\n\n\n\n<p>Examples:<br>Japanese maple \u2018Sango Kaku\u2019 (Japanese), known as coral bark Japanese maple in the United States.<br>Willow-leaf cotoneaster \u2018Herbst Feuer\u2019 (German), literally \u201cautumn fire.\u201d<br>Red maple \u2018October Glory\u2019 (United States).<\/p>\n\n\n\n<p><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>Hybrids<\/strong> (opens in new window)<\/a> are denoted by a \u201c\u00d7\u201d (cross) before the species name. Interspecific hybrids are a cross between two different species within the same genus. For instance, <em>Forsythia <\/em>\u00d7 <em>intermedia<\/em> (border forsythia) is the result of a cross between <em>Forsythia suspensa<\/em> (weeping forsythia) and <em>Forsythia viridissima<\/em> (greenstem forsythia).<\/p>\n\n\n\n<p>If a new hybrid cross has been given a name it may just have a genus \u00d7\u2018cultivar\u2019 name, as in the case of <em>Rhododendron<\/em> \u00d7 \u2018PJM\u2019; if it has not been given a cultivar name, it would be written <em>Rhododendron atlanticum<\/em> \u00d7 <em>periclymenoides<\/em>.<\/p>\n\n\n\n<p>An intergeneric or bigeneric hybrid is a cross between two genera, so in its name the \u00d7 is put before the genus. The new genus name is a combination of the genus names of the two parents.<\/p>\n\n\n\n<p>Examples:<br>\u00d7<em>Cuprocyparis leylandii <\/em>(formerly \u00d7<em>Cupressocyparis leylandii<\/em>) commonly known as the Leyland cypress. This is <em>Hesperocyparis macrocarpa<\/em> (formerly <em>Cupressus macrocarpa<\/em>) crossed with <em>Xanthocyparis nootkatensis<\/em> (formerly <em>Chamaecyparis nootkatensis<\/em>).<\/p>\n\n\n\n<p><em>Berberis<\/em> x <em>Aquisargentii<\/em>, is the result of many crosses between <em>Mahonia<\/em> and <em>Berberis<\/em>.<\/p>\n\n\n\n<p>+<em>Laburnocytisus adamii<\/em> is the result of a grafted hybrid: <em>Laburnum anagyroides<\/em> and Chamaecytisus purpureus (<em>Cytisus purpureus<\/em>). This intergeneric hybrid occurs above the graft union. A grafted hybrid is when a typical graft is made between root stock and scion but the root stock and scion actually begin to share a mixture of parental tissue. It is quite rare but has been reproduced with a tomato and black nightshade. Notice the \u201c+\u201d before the generic name, it indicates special hybrid status.<\/p>\n\n\n\n<p>Botanical names do sometimes change. When a person discovers or originates a new plant, that person gets to give the plant its botanical name by publishing the description and name of the plant in a scholarly journal. These journals range from very popular and widely read to rather obscure. If a plant is found and named in a journal that is not widely read, it may not be immediately noticed. That same plant may be \u201crediscovered\u201d by someone else at a later date, given a different name, and that name published in a very popular, widely read journal. The second name may become the accepted name. But by botanical rules, the first name is the valid name. If someone goes back in the literature and finds the original botanical name, the plant name should revert to that original botanical name as outlined in the International Code of Nomenclature for Algae, Fungi, and Plants, which is listed in the Further Reading section.<\/p>\n\n\n\n<p>An interesting example is our native Douglas-fir. First discovered by Archibald Menzies in 1792, it was named <em>Pinus taxifolia<\/em>. Later, they learned that it had been misidentified. <em>Pinus taxifolia<\/em> had already been attributed to another plant and therefore was an illegitimate name. Furthermore, Douglas-fir is not in the <em>Pinus<\/em> genus nor is it in the fir genera. It was recognized as a distinct and separate species and provided a new genus, <em>Pseudotsuga<\/em>, with <em>taxifolia<\/em> as the specific epithet (literally \u201cfalse hemlock\u201d + foliage like a yew). Following Menzies discovery, Meriwether Lewis collected samples during the Lewis and Clark Expedition in 1805\u201306, unaware that the Douglas-fir had already been discovered and described a few years previously. Then, in 1826, David Douglas brought back samples of the tree and named it after himself\u2014<em>Pseudotsuga douglasii<\/em>. When the ICN discovered the misnaming, the name was changed once again and is currently <em>Pseudotsuga menziesii<\/em> (named after its initial discoverer Archibald Menzies).<\/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-max-width--medium wsu-align-item--center wsu-spacing-after--large wsu-spacing-before--large\" >\r\n        \n\n<p class=\"has-text-align-left  wsu-font-size--medium\">Common names do not translate from one language into another. This includes American English to British English and vice versa.<br>Examples:<br><em>Tilia<\/em> species<br>German\u2014lindens, as in \u201cUnter den Linden\u201d<br>American English\u2014lindens<br>English\u2014lime trees<br><em>Sorbus aucuparia<\/em><br>German\u2014Vogelbeere, literally \u201cbird berry\u201d<br>American English\u2014European mountain ash<br>English\u2014rowan<\/p>\n\n<\/div>\r\n\n\n\n<p>Botanical names have also changed due to the introduction of DNA sequencing. Now with this extensive database, plants can be genetically compared and plant evolutionary relationships better understood. Names are being changed to reflect this new knowledge, like with Monterey cypress, Leyland cypress, and Alaska cedar.<\/p>\n\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch2-common-names\">Common Names<\/h2>\n\n\n\n<p>Standard botanical names are accepted worldwide. In comparison, common names are regional, vernacular, and confusing. The same common name may refer to many different plants, and conversely, the same plant may be known by many different common names.<\/p>\n\n\n\n<p>Some species do not have a common name and are usually called by their generic name. For example, <em>Idesia polycarpa<\/em> (a medium-sized, relatively rare, desirable landscape tree) is commonly just called idesia. Other popular plants that are known by their generic name include aster, coleus, forsythia, hibiscus, impatiens, iris, pachysandra, rhododendron, salvia, sedum, verbena, and viburnum.<\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--none wsu-spacing-before--none\">\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\/Fig_01-9.jpg\" alt=\"Manicured flower garden in bloom in a canyon environment. \" class=\"wp-image-3511\" width=\"450\" height=\"300\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_01-9.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_01-9-300x200.jpg 300w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 1. Plant forms and habit range from tall or spreading trees to upright or trailing herbaceous perennials to ground-hugging ivy. Photo: Paula Dinius\/WSU.<\/figcaption><\/figure><\/div>\n\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch2-diagnostic-plant-morphology\">Diagnostic Plant Morphology<\/h2>\n\n\n\n<p>Botanists use visible plant characteristics that can be described, measured, and compared to assess a plant for identification and classification purposes. There are many diagnostic characteristics, including such features as plant habit and form (Figure 1), leaf form and arrangements of leaves on a stem (Figures 3 and 4), flower types, flower forms and inflorescence types (Figure 5), and stem shape. Sometimes a certain characteristic is diagnostic for a plant family, such as square stems in the mint family.<\/p>\n\n\n\n<p>Plant habit and form is the shape, height, width, and branch architecture of the plant. As seen in Figure 1 and Figure 2, plants can range from tall and erect to low and creeping. Leaf form is the overall shape of the leaves, including lobes, margins, apex, and base; leaf attachment is the pattern in which the leaf is attached to the stem; and bud shape can range from pointed to rounded with or without bud scales covering the immature tissue as seen in Figure 3. Leaves can be identified as \u201csimple,\u201d which means that the leaf is single, or \u201ccompound,\u201d where the leaf blade is divided into leaflets. To determine whether a leaf is compound or simple, look at where the leaf attaches to the stem. At this point you will see a leaf bud in the leaf axil. Figure 4 shows different forms of compound leaves and a simple leaf for comparison.<\/p>\n\n\n\n<p>Flowers like daisies have radial symmetry and are called actinomorphic. Flowers like snapdragons have bilateral symmetry and are called zygomorphic. There are other forms, but these are the most common. A single flower on a stem or multiple flowers on a stem singularly or in clusters, in various patterns, is called the inflorescence. Figure 5 shows some common inflorescence types.<\/p>\n\n\n<div class=\"wsu-row wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n<div class=\"wp-block-image wsu-spacing-after--none\">\n<figure class=\"alignright size-large\"><img decoding=\"async\" loading=\"lazy\" width=\"407\" height=\"1024\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_02_plant_habits-1-407x1024.jpg\" alt=\"Plant habits and growth forms. From top to bottom: erect, prostrate, climbing, epiphytic, coppice shoots, stoloniferous, rhizomatous, suckers.\" class=\"wp-image-3513\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_02_plant_habits-1-407x1024.jpg 407w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_02_plant_habits-1-119x300.jpg 119w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_02_plant_habits-1.jpg 600w\" sizes=\"(max-width: 407px) 100vw, 407px\" \/><figcaption class=\"wp-element-caption\">Figure 2. Plant habits and growth forms. Photos: Noelle Hart\/WSU\u2014erect, prostrate, climbing, epiphytic, coppice shoots; Jim Kropf\/WSU\u2014stoloniferous, rhizomatous; Christine Hart\u2014suckers.<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column  wsu-color-background--gray-0 wsu-border--add-left wsu-border--color-vineyard\"  style=\"\">\r\n\t\n\n<h3 class=\"wp-block-heading has-text-align-center  wsu-font-size--xxmedium\">What\u2019s in a Name?<\/h3>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\">\u201cCedar\u201d is a common name used across several genera.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\"><em>Thuja plicata<\/em>, known variously as western red cedar and giant arborvitae.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\"><em>Xanthocyparis<\/em> (a.k.a. <em>Chamaecyparis<\/em>) <em>nootkatensis<\/em>, known variously as Alaska cedar and yellow cedar.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\"><em>Chamaecyparis lawsoniana<\/em> known as Port Orford cedar and Lawson\u2019s falsecypress.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\"><em>Chamaecyparis thyoides<\/em>, Atlantic white cedar.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\"><em>Cedrus<\/em> spp., commonly known as true cedars: atlas cedar, deodar cedar, cedar of Lebanon, etc.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\"><em>Cryptomeria japonica<\/em>, known as Japanese cedar.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\"><em>Juniperus virginiana<\/em>, eastern red cedar.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\"><em>Juniperus scopulorum<\/em>, western red cedar. (Notice the same common name as <em>Thuja plicata<\/em>, which actually is an arborvitae not a juniper.) This is also known as Rocky Mountain cedar and Rocky Mountain juniper.<\/p>\n\n\n\n<p class=\"wsu-font-size--medium wsu-spacing-after--xsmall\" id=\"block-9e2a73fd-efec-4a0d-8e81-b66cc13cdd38\">\u201cIronwood\u201d and \u201chornbeam\u201d are common names used for several species of trees. Below are two different plants with the same common name. Each plant also has different regional names:<\/p>\n\n\n\n<ol class=\"wsu-font-size--medium\">\n<li><em>Ostrya virginiana<\/em> over its range is known variously as ironwood and hornbeam.<\/li>\n\n\n\n<li><em>Carpinus caroliniana<\/em> over its range is known as ironwood and hornbeam, but also as blue beech (no relation to true beech).<\/li>\n<\/ol>\n\n<\/div>\r\n\n<\/div>\n\n\n<p class=\"wsu-font-size--xsmall wsu-spacing-before--large wsu-spacing-after--small\">Figure 3. Distinguishing leaf characteristics and terms. Illustrations by Gerald Steffen.<\/p>\n\n\n<div class=\"wsu-row wsu-row--quarters\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h4 class=\"wp-block-heading wsu-font-size--xxmedium wsu-spacing-after--xxmedium\">Leaf Arrangement<\/h4>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Elm-Branch.jpg\" alt=\"Elm tree branch with green leaves isolated on white background\" class=\"wp-image-3519\" width=\"225\" height=\"236\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Elm-Branch.jpg 300w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Elm-Branch-286x300.jpg 286w\" sizes=\"(max-width: 225px) 100vw, 225px\" \/><figcaption class=\"wp-element-caption\">Alternate\u2014Elm<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Arrangement-Birch.jpg\" alt=\"Young birch tree branches with leaves isolated on white background\" class=\"wp-image-3520\" width=\"155\" height=\"269\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Arrangement-Birch.jpg 300w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Arrangement-Birch-173x300.jpg 173w\" sizes=\"(max-width: 155px) 100vw, 155px\" \/><figcaption class=\"wp-element-caption\">Alternate\u2014Birch<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h4 class=\"wp-block-heading wsu-font-size--xxmedium wsu-spacing-after--xxmedium\">Bud Scales<\/h4>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/No-Scales-Sumac.jpg\" alt=\"Sumac branch with buds isolated on white background\" class=\"wp-image-3521\" width=\"92\" height=\"269\" \/><figcaption class=\"wp-element-caption\">None\u2014Sumac<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Bud-Scales-Cherry.jpg\" alt=\"Cherry tree branch with swollen buds on isolated white background\" class=\"wp-image-3522\" width=\"120\" height=\"266\" \/><figcaption class=\"wp-element-caption\">Many\u2014Cherry<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n<div class=\"wsu-row wsu-row--thirds\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h4 class=\"wp-block-heading wsu-font-size--xxmedium wsu-spacing-after--xxmedium\">Margins<\/h4>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"96\" height=\"267\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Olive-Branch.jpg\" alt=\"Green olive leaf isolated on white background\" class=\"wp-image-3524\" \/><figcaption class=\"wp-element-caption\">Entire\u2014Olive<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Apricot-leaf.jpg\" alt=\"Green apricot leaf isolated on white background\" class=\"wp-image-3525\" width=\"197\" height=\"263\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Apricot-leaf.jpg 300w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Apricot-leaf-225x300.jpg 225w\" sizes=\"(max-width: 197px) 100vw, 197px\" \/><figcaption class=\"wp-element-caption\">Serrate\u2014Apricot<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Double-Serrate-Elm.jpg\" alt=\"Green elm leaf isolated on white background\" class=\"wp-image-3526\" width=\"138\" height=\"280\" \/><figcaption class=\"wp-element-caption\">Double Serrate\u2014Elm<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n<\/div>\n\n<div class=\"wsu-row wsu-row--thirds\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Crenate-Beech-1.jpg\" alt=\"Green crenate beech leaf isolated on white background\" class=\"wp-image-3534\" width=\"142\" height=\"238\" \/><figcaption class=\"wp-element-caption\">Crenate\u2014Beech<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Double-Crenate-Alder-1.jpg\" alt=\"Green alder tree leaf isolated on white background\" class=\"wp-image-3535\" width=\"160\" height=\"234\" \/><figcaption class=\"wp-element-caption\">Double Crenate\u2014Alder<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Dentate-Aspen-1.jpg\" alt=\"Green quaking aspen leaf  isolated on white background\" class=\"wp-image-3536\" width=\"142\" height=\"233\" \/><figcaption class=\"wp-element-caption\">Dentate\u2014Aspen<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n<div class=\"wsu-row wsu-row--quarters\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h4 class=\"wp-block-heading wsu-font-size--xxmedium wsu-spacing-after--xxmedium\">Form<\/h4>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Silver-Maple.jpg\" alt=\"Green silver maple leaf isolated on white background\" class=\"wp-image-3537\" width=\"180\" height=\"214\" \/><figcaption class=\"wp-element-caption\">Simple\u2014Silver Maple<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Compound-Ash.jpg\" alt=\"Green Rowan leaf isolated on white background\" class=\"wp-image-3538\" width=\"130\" height=\"222\" \/><figcaption class=\"wp-element-caption\">Compound\u2014Ash<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h4 class=\"wp-block-heading wsu-font-size--xxmedium wsu-spacing-after--xxmedium\">Lobes<\/h4>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Oak-Leaf.jpg\" alt=\"Green Oak leaf isolated on white background\" class=\"wp-image-3539\" width=\"132\" height=\"223\" \/><figcaption class=\"wp-element-caption\">Pinnate\u2014Oak<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Palmate-Maple.jpg\" alt=\"Green maple leaf isolated on white background\" class=\"wp-image-3540\" width=\"200\" height=\"217\" \/><figcaption class=\"wp-element-caption\">Palmate\u2014Maple<\/figcaption><\/figure><\/div>\n\n\n<p class=\"has-text-align-center\"><\/p>\n\n<\/div>\r\n\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n<div class=\"wsu-row wsu-row--thirds\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h4 class=\"wp-block-heading wsu-font-size--xxmedium wsu-spacing-after--xxmedium\">Base<\/h4>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Uneven-Elm.jpg\" alt=\"Green asymmetrical elm leaf isolated on white background\" class=\"wp-image-3543\" width=\"170\" height=\"251\" \/><figcaption class=\"wp-element-caption\">Asymmetrical\u2014Elm<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Grape-Leaf.jpg\" alt=\"Green grape leaf isolated on white background\" class=\"wp-image-3544\" width=\"222\" height=\"241\" \/><figcaption class=\"wp-element-caption\">Heart\u2014Grape<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Rounded-Blueberry.jpg\" alt=\"Green blueberry leaf isolated on white background\" class=\"wp-image-3546\" width=\"138\" height=\"233\" \/><figcaption class=\"wp-element-caption\">Round\u2014Blueberry<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n<div class=\"wsu-row wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h4 class=\"wp-block-heading wsu-spacing-after--xxmedium wsu-font-size--xxmedium\">Apex<\/h4>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Round-Locust.jpg\" alt=\"Green locust tree leaf isolated on white background\" class=\"wp-image-3547\" width=\"122\" height=\"269\" \/><figcaption class=\"wp-element-caption\">Round\u2014Locust<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Pointed-Willow.jpg\" alt=\"Green pointed willow leaf isolated on white background\" class=\"wp-image-3548\" width=\"49\" height=\"275\" \/><figcaption class=\"wp-element-caption\">Pointed\u2014Willow<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n<div class=\"wsu-row wsu-row--quarters\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h4 class=\"wp-block-heading wsu-spacing-after--xxmedium wsu-font-size--xxmedium\">Shape<\/h4>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Apple-1.jpg\" alt=\"Green apple leaf isolated on white background\" class=\"wp-image-3550\" width=\"134\" height=\"243\" \/><figcaption class=\"wp-element-caption\">Ovate\u2014Apple<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Heart-Ivy-1.jpg\" alt=\"Green Ivy leaf isolated on white background\" class=\"wp-image-3551\" width=\"180\" height=\"236\" \/><figcaption class=\"wp-element-caption\">Heartshaped\u2014Ivy<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Pine.jpg\" alt=\"Pine tree branch isolated on white background\" class=\"wp-image-3553\" width=\"84\" height=\"238\" \/><figcaption class=\"wp-element-caption\">Linear\u2014Pine<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<p><\/p>\n\n\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Trangle-Poplar.jpg\" alt=\"Green poplar leaf isolated on white background\" class=\"wp-image-3554\" width=\"176\" height=\"227\" \/><figcaption class=\"wp-element-caption\">Triangular\u2014Poplar<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n<\/div>\n\n<div class=\"wsu-row wsu-row--quarters\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Lancolet-Willow.jpg\" alt=\"Green willow leaf isolated on white background\" class=\"wp-image-3555\" width=\"80\" height=\"386\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Lancolet-Willow.jpg 96w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Lancolet-Willow-62x300.jpg 62w\" sizes=\"(max-width: 80px) 100vw, 80px\" \/><figcaption class=\"wp-element-caption\">Lanceolate\u2014Willow<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Eliptical-Walnut.jpg\" alt=\"Green walnut tree leaf isolated on white background\" class=\"wp-image-3556\" width=\"170\" height=\"367\" \/><figcaption class=\"wp-element-caption\">Elliptical\u2014Walnut<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Scale-Cedar.jpg\" alt=\"Cedar tree branch isolated on white background\" class=\"wp-image-3557\" width=\"170\" height=\"347\" \/><figcaption class=\"wp-element-caption\">Scale-like\u2014Cedar<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n\n<div class=\"wsu-column\"  style=\"\">\r\n\t\n<div class=\"wp-block-image wsu-spacing-after--xxsmall\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Chestnut.jpg\" alt=\"Green carved horse chestnut leaf isolated on white background\" class=\"wp-image-3558\" width=\"170\" height=\"336\" \/><figcaption class=\"wp-element-caption\">Obovate\u2014Chestnut<\/figcaption><\/figure><\/div>\n<\/div>\r\n\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\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\/Fig_04-8.jpg\" alt=\"Diagram illustrating six types of simple or compound leaves and axillary bud attachment. Simple leaf with leaf bud is unnumbered. From top to bottom: (1) Pinnately compound leaflets have opposite attachment. (2) Bipinnately compound means a twice compound pinnate leaf. (3) Palmately compound means that leaflets are attached at center point. (4) Trifoliate refers to a set of three leaves with central attachment. (5) Trifoliate compound is a twice compound trifoliate leaf.\" class=\"wp-image-3562\" width=\"450\" height=\"749\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_04-8.jpg 600w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_04-8-180x300.jpg 180w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Figure 4. Types of compound leaves and axillary bud attachment. (1) Pinnately compound leaflets have opposite attachment. (2) Bipinnately compound means a twice compound pinnate leaf. (3) Palmately compound means that leaflets are attached at center point. (4) Trifoliate refers to a set of three leaves with central attachment. (5) Trifoliate compound is a twice compound trifoliate leaf. Diagram by Noelle Hart\/WSU.<\/figcaption><\/figure>\n\n<\/div>\r\n\n\n<div class=\"wsu-column  wsu-border--add-left wsu-border--color-vineyard\"  style=\"\">\r\n\t\n\n<h3 class=\"wp-block-heading has-text-align-center\">Sample of Inflorescence Types<\/h3>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"576\" height=\"739\" src=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_05_inflorescence_types.jpg\" alt=\"Examples of five inflorescence types in flowering plants. Capitulum\/head: dandelion and coneflower with radial symmetry. Spike: French lavender and common mullein with bilateral symmetry. Raceme: foxglove and lupine, bilateral symmetry. Umbel: ornamental onion and red-flowered cowslip, radial symmetry. Corymb: yarrow and candytuft, radial symmetry.\" class=\"wp-image-3563\" srcset=\"https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_05_inflorescence_types.jpg 576w, https:\/\/wpcdn.web.wsu.edu\/extension\/uploads\/sites\/62\/2025\/10\/Fig_05_inflorescence_types-234x300.jpg 234w\" sizes=\"(max-width: 576px) 100vw, 576px\" \/><figcaption class=\"wp-element-caption\">Figure 5. Examples of a few common inflorescence types. Photos a\u2013f and i by Noelle Hart\/WSU; photo g: <a rel=\"noreferrer noopener\" href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=19466456\" target=\"_blank\">Allium atropurpureum (opens in new window)<\/a> modified from JLPC\/Wikimedia Commons, CC BY-SA 3.0; photo h: <a rel=\"noreferrer noopener\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Red_flowered_cowslip.JPG\" target=\"_blank\">Red flowered cowslip (opens in new window)<\/a> modified from Jasper33, public domain; photo j: <a rel=\"noreferrer noopener\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:2010-06-29_(3)_Iberis_umbellata.jpg\" target=\"_blank\">Iberis umbellata (opens in new window)<\/a> modified from Vera Buhl; via Wikimedia Commons. Diagram created by Noelle Hart\/WSU. Table created by Paula Dinius\/WSU. Source: Harris and Harris 2001.<\/figcaption><\/figure>\n\n<\/div>\r\n\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n\n\n<div class=\"wsu-row wsu-row--halves\" >\r\n    \n<div class=\"wsu-column\"  style=\"\">\r\n\t\n\n<h2 class=\"wp-block-heading  wsu-heading--style-marked\" id=\"ch2-identification-keys\">Identification Keys<\/h2>\n\n\n\n<p class=\" wsu-max-width--xmedium\">Plant identification keys are tools for identifying an unknown plant. There are several types of identification keys. For instance, a random access key asks numerous, specific questions about the plant in question and presents a list of possible answers. An example of a dichotomous key for identifying trees can be found online at the <a rel=\"noreferrer noopener\" href=\"https:\/\/biology.burke.washington.edu\/herbarium\/imagecollection\/keys.php?Key=1\" data-type=\"URL\" data-id=\"https:\/\/biology.burke.washington.edu\/herbarium\/imagecollection\/keys.php?Key=1\" target=\"_blank\">Burke Museum of Natural History and Culture (opens in new window)<\/a> at the University of Washington.<\/p>\n\n\n\n<p class=\" wsu-max-width--xmedium\">Probably the most common type of identification key is the dichotomous key, which offers two contradictory descriptive statements, called leads. To correctly use a dichotomous key, you must choose one of the two options (both cannot be true of the specimen in question). These contradictory sets are called couplets.<\/p>\n\n\n\n<p class=\" wsu-max-width--xmedium\">Each couplet starts with the same characteristic of the plant, such as leaves, in\ufb02orescences, \ufb02owers, buds, fruit, or some other morphological characteristic. The user must choose which lead fits the plant in question. The user must then consider the next couplet, then the next, and so on, until the plant is keyed out. Keys and their couplets may be either numbered or lettered. An example of a dichotomous key for identifying trees can be found online at <a href=\"http:\/\/oregonstate.edu\/trees\/ dichotomous_key.html\" data-type=\"URL\" data-id=\"http:\/\/oregonstate.edu\/trees\/ dichotomous_key.html\" target=\"_blank\" rel=\"noreferrer noopener\">Oregon State University\u2019s Common Trees of the Pacific Northwest website (opens in new window)<\/a>.<\/p>\n\n\n\n<p class=\" wsu-max-width--xmedium\">There are keys that require access to all parts of the plant\u2014flower, fruit, leaves, etc. Other keys use only limited plant parts, such as stem, leaf, and buds. It is important to be aware that all types of keys have limitations, and identification should be confirmed using multiple reliable sources.<\/p>\n\n\n\n<p class=\" wsu-max-width--xmedium\">There are also plant identification apps available to download onto a smart phone. By taking a picture of the plant in question the image recognition software is able to identify it. App users are encouraged to check their work by using an identification key or other reliable sources when identifying unknown plants. West Virginia University\u2019s article \u201c<a rel=\"noreferrer noopener\" href=\"https:\/\/medicine.hsc.wvu.edu\/News\/Story?headline=plant-and-flower-identification-apps\" target=\"_blank\">Plant and Flower Apps (opens in new window)<\/a>\u201d explains more about using apps and various options.<\/p>\n\n<\/div>\r\n\n\n<div class=\"wsu-column  wsu-border--add-left wsu-border--color-vineyard wsu-color-background--gray-0\"  style=\"\">\r\n\t\n\n<h3 class=\"wp-block-heading has-text-align-center wsu-font-size--xxmedium wsu-spacing-after--small\">An Identification Key<\/h3>\n\n\n\n<p class=\"wsu-font-size--medium\">This is a very simple key used to distinguish eight broadleaf evergreen plants.<\/p>\n\n\n\n<p><strong>1.<\/strong> Leaves opposite<\/p>\n<p style=\"margin-left: 1.5em\"><strong>2.<\/strong> Leaves mostly less than 1 5\/8 inch<\/p>\n<p style=\"margin-left: 3em\"><strong>3.<\/strong> Leaf margins toothed<\/p>\n<p style=\"margin-left: 4.5em\"><strong>4.<\/strong> Leaf margins spiny toothed (dentate)<br \/><em>Osmanthus delavayi<\/em>, Delavey\u2019s osmanthus<\/p>\n<p style=\"margin-left: 4.5em\"><strong>4.<\/strong> Leaf margins crenate<br \/><em>Euonymus fortunei<\/em>, creeping euonymus<\/p>\n<p style=\"margin-left: 3em\"><strong>3.<\/strong> Leaf margins entire<br \/><em>Buxus sempervirens<\/em>, boxwood<\/p>\n<p style=\"margin-left: 1.5em\"><strong>2.<\/strong> Leaves more than 1 5\/8 inch<br \/><em>Viburnum davidii<\/em>, David viburnum<\/p>\n<p><strong>1.<\/strong> Leaves alternate<\/p>\n<p style=\"margin-left: 1.5em\"><strong>5.<\/strong> Leaves mostly less than 2 3\/8 inch<\/p>\n<p style=\"margin-left: 3em\"><strong>6.<\/strong> Stems armed (thorny)<br \/><em>Pyracantha<\/em> sp., firethorn<\/p>\n<p style=\"margin-left: 3em\"><strong>6.<\/strong> Stems not armed<\/p>\n<p style=\"margin-left: 4.5em\"><strong>7.<\/strong> Leaves oblanceolate<br \/><em>Pieris japonica<\/em>, Japanese andromeda<\/p>\n<p style=\"margin-left: 4.5em\"><strong>7.<\/strong> Leaves ovate<br \/><em>Vaccinium ovatum<\/em>, evergreen huckleberry<\/p>\n<p style=\"margin-left: 1.5em\"><strong>5.<\/strong> Leaves greater than 2 3\/8 inch<\/p>\n<p style=\"margin-left: 3em\"><strong>8.<\/strong> Leaves ovate<br \/><em>Prunus lusitanica<\/em>, Portuguese laurel<\/p>\n<p style=\"margin-left: 3em\"><strong>8.<\/strong> Leaves obovate<br \/><em>Prunus laurocerasus<\/em>, cherry (English) laurel<\/p>\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=\"ch2-further-reading\">Further Reading<\/h2>\n\n\n\n<p><a href=\"https:\/\/pubs.extension.wsu.edu\/gardening\" data-type=\"URL\" data-id=\"https:\/\/pubs.extension.wsu.edu\/gardening\" target=\"_blank\" rel=\"noreferrer noopener\">WSU Extension Publications (opens in new window)<\/a><\/p>\n\n\n\n<p>Albers, J.J. 2021. <em>Growing Conifers. The Complete Illustrated Gardening and Landscaping Guide.<\/em> New Society Publishers.<\/p>\n\n\n\n<p>Bailey, L.H., and E.Z. Bailey. 1976. <em>Hortus Third: A Concise Dictionary of Plants Cultivated in the United States and Canada.<\/em> Macmillan Publishing Company.<\/p>\n\n\n\n<p>Bienz, D.R. 1993. <em>The Why and How of Home Horticulture.<\/em> W.H. Freeman and Co.<\/p>\n\n\n\n<p>Brickel, C., and J.D. Zuk, eds. 2004. <em>The American Horticultural Society A\u2013Z Encyclopedia of Garden Plants.<\/em> Revised edition. DK Publishing.<\/p>\n\n\n\n<p>Brun, C., C. Daniels, and T. Kohlhauff. 2016. <a rel=\"noreferrer noopener\" href=\"https:\/\/pubs.extension.wsu.edu\/a-guide-to-washington-states-urban-tree-canopy\" data-type=\"URL\" data-id=\"https:\/\/pubs.extension.wsu.edu\/a-guide-to-washington-states-urban-tree-canopy\" target=\"_blank\">A Guide to Washington State\u2019s Urban Tree Canopy (opens in new window)<\/a>. Washington State University Extension Publication EM107E. Washington State University.<\/p>\n\n\n\n<p>Brun, C., and P. Dinius. 2015. <a rel=\"noreferrer noopener\" href=\"https:\/\/pubs.extension.wsu.edu\/product\/selecting-plants-for-screens-and-hedges-home-garden-series\/\" data-type=\"URL\" data-id=\"https:\/\/pubs.extension.wsu.edu\/product\/selecting-plants-for-screens-and-hedges-home-garden-series\/\" target=\"_blank\">Selecting Plants for Screens and Hedges (opens in new window)<\/a>. <br>Washington State University Extension Publication EM089E. Washington State University. <\/p>\n\n\n\n<p><a rel=\"noreferrer noopener\" href=\"https:\/\/biology.burke.washington.edu\/herbarium\/imagecollection\/keys.php?Key=1\" data-type=\"URL\" data-id=\"https:\/\/biology.burke.washington.edu\/herbarium\/imagecollection\/keys.php?Key=1\" target=\"_blank\">Burke Museum of Natural History and Culture (opens in new window)<\/a>. 2021. <br>Random Access Identification Key. University of Washington.<\/p>\n\n\n\n<p>Capon, B. 2010. <em>Botany for Gardeners.<\/em> 3rd edition. Timber Press.<\/p>\n\n\n\n<p>Coombs, C.J. 1992. <em>Trees.<\/em> DK Publishing.<\/p>\n\n\n\n<p>Dirr, M.A. 1998. <em>Manual of Woody Landscape Plants.<\/em> 5th edition. Stipes Publishing Co.<\/p>\n\n\n\n<p>DiTomaso, J.M., and E.A. Healy. 2007. <em>Weeds of California and Other Western States.<\/em> <br>University of California Agriculture and Natural Resources.<\/p>\n\n\n\n<p>Elpel, T.J. 2013. <em>Botany in a Day.<\/em> Hops Press LLC.<\/p>\n\n\n\n<p>Harris, J.G., and M. Harris. 2000. <em>Plant Identification Terminology.<\/em> 2nd edition. <br>Spring Lake Publishing.<\/p>\n\n\n\n<p>Hermann, R.K. 1982. <em>The Genus Pseudotsuga: Historical Record and Nomenclature.<\/em> <br>Oregon State University Forestry Research Laboratory.<\/p>\n\n\n\n<p>Hitchcock, C.L., and A. Cronquist. 1973. <em>Flora of the Pacific Northwest.<\/em> <br>University of Washington Press.<\/p>\n\n\n\n<p><a href=\"https:\/\/www.itis.gov\/\" data-type=\"URL\" data-id=\"https:\/\/www.itis.gov\/\" target=\"_blank\" rel=\"noreferrer noopener\">Integrated Taxonomic Information System Report (opens in new window)<\/a>. n.d.<\/p>\n\n\n\n<p><a rel=\"noreferrer noopener\" href=\"https:\/\/www.iapt-taxon.org\/nomen\/main.php\" data-type=\"URL\" data-id=\"https:\/\/www.iapt-taxon.org\/nomen\/main.php\" target=\"_blank\">International Code of Nomenclature for Algae, Fungi, and Plants (opens in new window)<\/a>. 2018. <br>International Association for Plant Taxonomy.<\/p>\n\n\n\n<p><a href=\"https:\/\/treesandshrubsonline.org\/articles\/laburnocytisus\/laburnocytisus-adamii\/\" data-type=\"URL\" data-id=\"https:\/\/treesandshrubsonline.org\/articles\/laburnocytisus\/laburnocytisus-adamii\/\" target=\"_blank\" rel=\"noreferrer noopener\">International Dendrology Society (opens in new window)<\/a>. n.d. Trees and Shrubs Online.<\/p>\n\n\n\n<p>Jensen, E., D. Zahler, B. Patterson, and B. Littlefield. 2010. <a href=\"http:\/\/oregonstate.edu\/trees\/dichotomous_key.html\" data-type=\"URL\" data-id=\"http:\/\/oregonstate.edu\/trees\/dichotomous_key.html\" target=\"_blank\" rel=\"noreferrer noopener\">Common Trees of the Pacific Northwest: Dichotomous Key (opens in new window)<\/a>. Oregon State University.<\/p>\n\n\n\n<p>Kruessmann, G. (1986) 1978. <em>Cultivated Broad-Leaved Trees and Shrubs.<\/em> Translated. Timber Press.<\/p>\n\n\n\n<p>Kruessmann, G. 2009. <em>Manual of Cultivated Conifers.<\/em> Timber Press.<\/p>\n\n\n\n<p>Mabberley, D.J. 2008. <em>Mabberley\u2019s Plant-Book.<\/em> 3rd edition. Cambridge University Press.<\/p>\n\n\n\n<p>National Audubon Society. 2021. <em>Trees of North America.<\/em> Knopf Publisher.<\/p>\n\n\n\n<p><a href=\"https:\/\/plants.ces.ncsu.edu\/plants\/x-mahoberberis-aquisargentii\/\" data-type=\"URL\" data-id=\"https:\/\/plants.ces.ncsu.edu\/plants\/x-mahoberberis-aquisargentii\/\" target=\"_blank\" rel=\"noreferrer noopener\">North Carolina State University Extension Gardener Plant Toolbox (opens in new window)<\/a>. n.d.<\/p>\n\n\n\n<p>Phillips, R., and M. Rix. 2008. <em>Perennials: The Definitive Reference with Over 2,500 Photographs.<\/em> Firefly Books.<\/p>\n\n\n\n<p>Ritter, M. 2023. <a href=\"https:\/\/www.pacifichorticulture.org\/articles\/why-plant-names-change-2\/\" data-type=\"URL\" data-id=\"https:\/\/www.pacifichorticulture.org\/articles\/why-plant-names-change-2\/\" target=\"_blank\" rel=\"noreferrer noopener\">Why Plant Names Change (opens in new window)<\/a>. Pacific Horticulture.<\/p>\n\n\n\n<p><a href=\"https:\/\/powo.science.kew.org\/taxon\/urn:lsid:ipni.org:names:485979-1\" data-type=\"URL\" data-id=\"https:\/\/powo.science.kew.org\/taxon\/urn:lsid:ipni.org:names:485979-1\" target=\"_blank\" rel=\"noreferrer noopener\">Royal Botanical Gardens Kew Plants of the World Online (opens in new window)<\/a>. n.d. Chamaecytisus purpureus (Scop.)<\/p>\n\n\n\n<p>Still, S.M. 1994. <em>Manual of Herbaceous Ornamental Plants.<\/em> 4th edition. Stipes Publishing.<\/p>\n\n\n\n<p><a href=\"https:\/\/plants.sc.egov.usda.gov\/home\" data-type=\"URL\" data-id=\"https:\/\/plants.sc.egov.usda.gov\/home\" target=\"_blank\" rel=\"noreferrer noopener\">US Department of Agriculture (opens in new window)<\/a>. Plant Database. 2021.<\/p>\n\n\n\n<p>Vertrees, J.D., and P. Gregory. 2010. <em>Japanese Maples: The Complete Guide to Selection and Cultivation.<\/em> 4th edition. Timber Press.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Paula Dinius, Urban Horticulturist, Chelan County Extension, Washington State University Introduction The primary purpose of this chapter is to acquaint you with methods of identifying plants and plant materials commonly used for landscape purposes. While most of the principles in plant identification may be botanical in nature, the ultimate objective is to determine the genus [&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\/562"}],"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=562"}],"version-history":[{"count":99,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/pages\/562\/revisions"}],"predecessor-version":[{"id":4438,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/pages\/562\/revisions\/4438"}],"wp:attachment":[{"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/media?parent=562"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/categories?post=562"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/extension.wsu.edu\/pnw-gardeners-handbook\/wp-json\/wp\/v2\/tags?post=562"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}