{"id":733,"date":"2025-07-17T14:43:23","date_gmt":"2025-07-17T21:43:23","guid":{"rendered":"https:\/\/extension.wsu.edu\/wrlp\/?page_id=733"},"modified":"2025-09-29T15:26:53","modified_gmt":"2025-09-29T22:26:53","slug":"buffercasestudy","status":"publish","type":"page","link":"https:\/\/extension.wsu.edu\/wrlp\/buffercasestudy\/","title":{"rendered":"Riparian Buffer Case Study – Nehalem River Ranch"},"content":{"rendered":"\n

T<\/em>This case study was developed by the USDA Forest Service, National Agroforestry Center<\/a> and the USDA Northwest Climate Hub<\/a>. Any errors or omissions are the responsibility of the authors and can be directed to the National Agroforestry Center. The lead author is Katherine Favor, ORISE Fellow with the National Agroforestry Center.<\/p>\n\n\n\n

These and more case studies were developed for the Pacific Northwest Training Manual for Applied Agroforestry (to be released in 2026).<\/em><\/p>\n\n\n\n

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Trees and shrubs planted in multiple rows form a riparian forest buffer between Nehalem River Ranch and the Nehalem River. Courtesy photo: Mitchel Davidovitz<\/figcaption><\/figure>\n\n\n\n

Introduction<\/h2>\n\n\n\n

Nehalem River Ranch is a 100-acre diversified ranch along the Nehalem River in Northwest Oregon, owned and managed by Jared Gardner. Jared has implemented several agroforestry practices on his land, including silvopasture, windbreaks, and riparian forest buffers<\/em> \u2013 managed areas of trees and shrubs that are located in between agricultural production and waterways for the purpose of water quality protection, streambank stabilization, wildlife habitat, and more (USDA National Agroforestry Center 2025). \u201cBeing stewards of 100 acres along a river is really magical, but it also comes with a responsibility,\u201d says Jared. \u201cWe are excited to do our part to keep the river as clean as possible.\u201d <\/p>\n\n\n\n

Focusing on diversity, Jared raises grass-fed and finished Angus-Hereford cross beef and Gloucestershire Old Spot cross pigs, and he also keeps bees for honey. Additionally, he partners with tenant farmers who lease shared pastureland and graze poultry in rotation behind his cattle and pigs. Along the river\u2019s edge, the ranch\u2019s riparian forest buffer serves as a barrier between the pastureland and the Nehalem River. The buffer filters runoff, reduces nutrient pollution, and stabilizes the riverbank to prevent erosion. It also supports Jared\u2019s honey operation by providing a year-round supply of flowers for his honeybees. <\/p>\n\n\n\n

Jared\u2019s goals for his land are to produce healthy, local meat and honey, and to foster a biodiverse landscape that supports both his farm and the surrounding Nehalem River watershed. \u201cThis has been a really important ecological site, culturally and historically,\u201d says Jared. \u201cIt\u2019s our responsibility to think about the river, the riparian zone, and how we steward animals and plants in relation to the riparian ecosystem.\u201d <\/p>\n\n\n\n

How it Started<\/h2>\n\n\n\n

When Jared purchased Nehalem River Ranch in 2014, the riverbanks on his property had already experienced significant ecological degradation. Much of the land\u2019s native woody perennial vegetation had been removed and converted into more pasture for cattle. Over time, much of the riverbank was overtaken by Japanese knotweed (Polygonum cuspidatum<\/em>) \u2013 a bamboo-like invasive forb. The roots of Japanese knotweed are connected to weak rhizomes that easily break apart (Colleran et al. 2020). Without the stronger roots of woody perennials to help stabilize the soil and hold it in place, streambank erosion became a significant issue. Motivated to address the erosion and invasive species issues, Jared began a large-scale restoration effort. In partnership with several local organizations, he removed the knotweed through mowing and targeted, intensive grazing, and planted in its place over 5,000 native trees and shrubs to rebuild the river\u2019s natural riparian buffer and stabilize the soil. <\/p>\n\n\n\n

Jared\u2019s restoration efforts were also aimed at improving habitat for terrestrial and aquatic wildlife. The woody perennials in the riparian forest buffer provide shelter and food to many terrestrial animals like elk, deer, and birds. The riparian forest buffer also filters runoff and reduces the amount of nutrients that end up in the river. This helps to prevent eutrophication \u2013  an accumulation of nutrients that leads to increased growth of algae, which can deplete oxygen levels and harm aquatic life. By reducing nutrient overload from livestock waste, the buffer protects aquatic organisms. <\/p>\n\n\n\n

Jared was also interested in planting trees along the river to cast shade and lower water temperatures, further improving conditions for aquatic organisms. He recognizes that improving habitat for wildlife does more than just benefit the environment \u2013 it also benefits the ranch itself. \u201cThe more trees we plant, the more birds of prey we have. The more birds of prey we have, the less gopher holes and tripping hazards for our cows,\u201d Jared explains. \u201cSo, it\u2019s little, simple things like that that are a win-win for both the ecology and our production.\u201d<\/p>\n\n\n\n

Design<\/h2>\n\n\n\n

The riparian forest buffer at Nehalem River Ranch spans the entire length of the river border \u2013 over 7,000 linear feet in total. The trees and shrubs were planted in rows varying from two to six rows wide, depending on the topography of the land. Within rows, trees were planted close together \u2013 just six to 10 feet apart \u2013 to account for expected losses due to elk browsing and other pressures. \u201cWe over-planted instead of using protective cages,\u201d says Jared. \u201cWe know that we will need to thin some trees down the line, but when we did the math, this method was more cost effective than having to pay for caging.\u201d All in all, six of Nehalem River Ranch\u2019s 100 acres are planted to riparian forest buffers. <\/p>\n\n\n\n

Species selection was an important part of the design process. In the rows closest to the river, Jared chose native plants with deep roots that could tolerate seasonally saturated soils, like:<\/p>\n\n\n\n