What is Agroforestry? And Why Would Forest Owners Care?

By Patrick Shults, Extension Forester, Washington State University, patrick.shults@wsu.edu

Silvopasture, forest farming, agroforestry … you may have heard these terms thrown around before. But what do they mean?

“Agroforestry” in its simplest definition is a land management method that integrates forestry and agriculture into the same production system (“agriculture” + “forestry” = agroforestry). This means that the different parts (trees, livestock, crops) are intentionally managed together in a way that promotes positive interactions and minimizes competition.

When done correctly, agroforestry can both diversify and maximize production for a landowner while improving soil quality, wildlife habitat, biodiversity, and a host of other ecosystem services.

While it may seem like a new concept, it is only newly popular in the U.S. and other temperate climates. The concept of agroforestry is actually quite old and has been used by native cultures for centuries, including in North America.

In tropical climates, it continues to be a popular form of land management for sustainably producing food, fiber, and fuel on small plots. However, on-the-ground practices look quite different in temperate climates compared to the tropics.

I’ve listed out the five most common agroforestry practices used in temperate countries and given them brief descriptions. Though some are geared towards agricultural producers who may want to introduce trees to their cropping systems, all offer opportunities for forest owners to diversify what they do on their lands.

Windbreaks

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This windbreak is protecting an agricultural field in the Upper Midwest. (Photo by the University of Minnesota Extension)

Windbreaks (or wind rows) are the first modern agroforestry practice to take place in the United States and were widely used during the Dust Bowl in the 1930s to reduce soil erosion in the Midwest.

This practice involves planting single or multiple rows of trees and/or shrubs which modify wind movement in your cropping system. Besides reducing erosion, they can also protect crops from damaging winds, reduce pesticide drift and livestock odors, provide wildlife habitat, provide fuelwood, and, in some cases, even improve crop production by regulating soil and air temperature.

Riparian Buffers and/or Forest Farming

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These log structures are part of a shitake mushroom forest farming operation at Wildcat Creek Tree Farm in McCleary. (Photo by Patrick Shults)

Another practice that primarily serves a “protective” purpose with additional benefits, riparian buffers are used to reduce pesticide and fertilizer runoff into waterways throughout agricultural lands in the Midwest. This requires a buffer of trees, shrubs, and ground flora surrounding streams, ponds, wetlands, and other important water resources on your property.

As forest owners in Washington State, pesticide and fertilizer runoff may not be as big of a concern. Moreover, you may already have a mandated forested buffer on your stream if it is considered fish-bearing.

Regardless, buffers like these protect waterways effectively and also serve as an opportunity for another agroforestry practice, forest farming. In the Appalachians and Midwest, forest farming often involves manipulating the forest canopy to foster valuable native plant species that require a shaded forest setting, such as ginseng or goldenseal.

In the Pacific Northwest, this practice could be used to produce non-timber forest products like berries, mushrooms, fuelwood, and valuable floral products.

Silvopasture

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Cows graze between rows of pine trees at an Alabama farm. (Photo by the Alabama Cooperative Extension System)

Likely the most common existing agroforestry practice for landowners in Washington state, silvopasture is the integration of livestock, trees, and forage. Although they may not call it silvopasture, many landowners run their livestock through their woodlots in both Eastern and Western Washington.

When done more intentionally, silvopasture provides considerable benefits to producers interested in selling both timber and livestock products. Trees provide protection and help to regulate air temperature which allows livestock to expend less energy heating and cooling their bodies.

The reduced stress for the animals can lead to greater milk production, reaching target weights quicker, and higher conception rates. Additionally, it allows a rancher to produce a long-term timber product or a forest owner to produce short-term income from livestock.

Although from both perspectives it may mean raising fewer cattle or fewer trees, the diversified and combined income can surpass that of growing only trees or raising only cattle.

Implementing silvopasture can be tricky, particularly in Western Washington, where the soils are more susceptible to compaction. More resources are available at the end of this article.

Alley Cropping

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Walnut trees and corn plants are planted in alley crops at a Minnesota farm. (Photo by the University of Minnesota Extension)

This practice involves growing high-value timber, veneer, or fruit and nut trees at a wide spacing to create “alleys” in which you can produce agricultural crops. In the Southeast, where agroforestry is increasingly popular, this may mean growing things like corn, soybeans, or tomatoes between rows of black walnut trees. In Washington, this may mean growing crops between rows of Douglas-fir, Ponderosa pine, or other native species.

Alley cropping is yet another way for landowners to diversify and increase income on their lands while sacrificing minimal growing space for trees. When done correctly it provides short and long-term products, improved soil nutrient cycling, biodiversity, wildlife habitat, and, in some cases, improved crop yields.

These five practices are considered the pillars of temperate agroforestry, but truthfully it is a wide umbrella with significant room for creativity, which appeals to some landowners.

Every parcel is unique and comes with special challenges. The flexibility of agroforestry allows landowners to find the approach that best fits their situation.

Why Should a Forest Owner Care?

Agroforestry is not for everyone.

But for landowners looking to diversify their production for commercial or personal use, agroforestry may be a viable option to do so without sacrificing significant tree-growing space. Agroforestry practices are catching on throughout modern and developing countries because they can often create a “win-win” scenario that makes both the landowners and the land more resilient to economic and environmental changes.

Despite their many benefits, these practices can be difficult to implement and require considerable forethought, planning, and, often, years of trial and error.

Because it is a relatively new area of research and every situation is unique, there is often limited information and recommendations available to landowners. This is especially true in the Pacific Northwest, which has trailed behind areas like the Midwest and Southeast in widescale implementation.

So, while it is likely not a good idea for an inexperienced landowner to turn their entire 20-acre forest or farm into an agroforestry operation at once, I would encourage interested landowners to do their research, seek professional help, and begin experimenting in small ways.

If you’d like to read more, below are links to available resources and publications.  For the very interested folks, check out the 2019 North American Agroforestry Conference in Corvallis this June.

Additional Resources:

Silvopasture: An Agroforestry Practice – Oregon State University

Agroforestry in the Pacific Northwest – U.S. Forest Service

National Agroforestry Center

University of Missouri – Center for Agroforestry

Association for Temperate Agroforestry

Regional Partnership Brings Assistance to Southwest Washington Forest Landowners

By Mike Kuttel, Jr., Farm Bill Coordinator, Washington Department of Fish and Wildlife, michael.kutteljr@dfw.wa.gov

Are you a forest landowner interested in technical or financial assistance to work on stewardship practices? The Southwest Washington Small Forest Lands Conservation Partnership is available to help.

This effort is part of the Natural Resources Conservation Service’s Regional Conservation Partnership Program and covers eight counties.  The Washington State Department of Natural Resources, Washington State Conservation Commission, Washington State University Extension, Washington Department of Fish and Wildlife, and eight conservation districts are partnering with NRCS to deliver the program.

The RCPP is voluntary and incentive-based. The NRCS and the state agencies pay four stewardship foresters to provide technical assistance and a WSU Extension Forester to provide outreach and education.

Financial assistance from NRCS and state programs is available to implement stewardship practices to improve forest health, water quality, and wildlife habitat. Cost share is available through NRCS’s Environmental Quality Incentives Program and Conservation Stewardship Program.

The Family Forest Fish Passage Program through DNR is available to correct fish passage barriers. Forest conservation easements through the NRCS Healthy Forests Reserve Program are also available. This program may provide regulatory predictability to forest landowners who conserve habitat for marbled murrelet, northern spotted owl, or fisher.

For more information, please visit our web app to contact your local RCPP stewardship forester.

southwest map

 

Announcements, Events, and Other News

2019 Forest Owner Field Days

The annual Family Forest Field Day attracts hundreds of landowners from all around the region to learn about a variety of forestry topics in a hands-on setting, including forest health, wildlife habitat and management, thinning and pruning, chainsaw safety, noxious weed management, and more.

Deary, ID – Saturday, June 22 (registration open)

Arlington, WA – Saturday, August 10 (details coming)

McCleary, WA – Saturday, August 24 (registration open)

Forest Health and Wildfire Seminars

Learn what makes forests healthy or unhealthy and how to recognize when there’s a problem on your property. Topics include insects, diseases, and drought, including their environmental roles and the important interactions between them. Learn about what property owners should do (and not do) to increase tree resilience and mitigate impacts.

Forest Stewardship Coached Planning

If you own wooded property, our flagship course will teach you how to assess your trees, avoid insect and disease problems, and attract wildlife. State experts will help you develop your own Forest Stewardship Plan to keep your woods on track to provide enjoyment and income for years to come.

  • Preston – Tuesdays starting September 10
  • Vashon – Mondays starting September 23
  • Cowlitz County – Location and details TBD

Other Events

Hands-On Chainsaw Safety and Maintenance Workshop – Okanogan, June 21-22

Can’t find the event you were looking for? Visit forestry.wsu.edu or contact patrick.shults@wsu.edu.

Helping Landowners Learn From Their Peers About Harvest Options

Northwest Natural Resource Group and Oregon State University are reaching out to forest owners for a voluntary study about timber harvesting methods to understand how they affect both financial and forest health outcomes.

The goal of this research project is to help landowners who are considering a timber harvest to learn from the experiences of others. There is limited information about the economics of commercial timber harvests that use thinning or uneven-aged management, and how those results compare with other harvest methods.

The researchers are looking to survey Oregon and Washington forest owners who harvested timber from their forest in the past five years (since 2014) and are willing to share information about the silvicultural methods and financial outcomes from these recent timber harvests. The survey asks detailed questions about the harvest techniques and equipment used, the volume of timber harvested, cost of the harvest work, and the harvest revenues.

The results of this study will be shared with forest owners through a variety of methods including articles, papers, and classes taught by NNRG, OSU, and partner organizations. Data in the study will remain confidential within the research team. Information will be aggregated so it cannot be traced to any individual ownership. Data will be collected from through June 2019.

If you are willing to share recent harvest information with NNRG and OSU, contact Lindsay Malone, one of the project researchers, at lindsay@nnrg.org. Lindsay can provide you with a copy of the survey.

Learn more about this research project at nnrg.org/thinning_study

Lindsay Malone, Director of Programs, Northwest Natural Resource Group, lindsay@nnrg.org

You’ve Got Soil Questions, and We’ve Got Answers

If you want to know how to access soil information for your property, work with multiple soils, or learn how to adapt your forest management for the soils you have, the USDA has online resources available to all that can help guide you through those processes.

Q: How can I access soil information for my property?

A: The U.S. Department of Agriculture publishes soil survey data online through a platform called Web Soil Survey. Although some areas are still undergoing initial mapping, the vast majority of private lands in the Pacific Northwest have soil survey data available. The data is available to the public, and best of all, it’s free! The following steps will help you obtain soils information for your property:

Step 1: Start Web Soil Survey by going to websoilsurvey.sc.egov.usda.gov/App/HomePage.htm. Click the large green “START WSS” button.

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Step 2: Define your area of interest (AOI). This is the area for which you will be obtaining soil survey data. You can simply enter an address or select a state/county, click “view”, and then zoom to your desired location on the map. Other navigation options are also available, although these methods are the most common and user-friendly.

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Once you are zoomed to your property or desired location, click the rectangular AOI tool to drag a box or use the polygon AOI tool to click around your select your AOI.

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The rectangle or polygon you select should then look like this:

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Step 3: View your soil map. Click the “Soil Map” tab at the top of your screen to see the soil survey map for your AOI. The map unit legend will appear on the left side of your screen. Clicking on the name of a map unit in the legend will open a window containing a description of that map unit and its individual soil components.

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Q: The soil map unit covering my property has multiple soils in it. How do I know which one I am working with?

A: In order to answer this question effectively I first need to clarify what exactly a “map unit” is, as well as explain the different types of map units used in soil surveys.

A map unit is a collection of areas defined and named the same in terms of their soil components (unique soil types) and/or miscellaneous (“non-soil”) areas. Each polygon delineated on a soil map is assigned a label or symbol that corresponds to a map unit. There are four general types of map units, however, for the purpose of this discussion I will focus on the three most commonly seen in soil survey products.

Consociations are map units dominated by a single soil component. A consociation may include minor components that occupy a relatively small (< 15%) percentage of the map unit area, but the map unit name will contain only the name of the dominant soil. Complexes and associations are map units consisting of two or more dissimilar components that occur in a consistent repeating pattern. The soil components comprising a complex cannot be separated at the mapping scale, while the components of an association can be; however, due to land use or user needs, they are not. Both of these map unit types may also include minor components. The map unit names for complexes and associations will contain the names of multiple soils.

Now to answer the original question: The map unit description (accessible by following step 3 above) will provide descriptions of typical site the soil characteristics for each component in the map unit. The type of map unit covering your property can be inferred from the map unit name. If the map unit is a consociation, the soil component that you are most likely working with is going to be the single dominant component for that map unit. However, if the specific area on your property is not representative of the map unit’s typical landscape/landform, you may be working with a minor component.

If the map unit covering your property is a complex or association, you will have to look at the map unit description to determine the component(s) you are working with. Soils tend to correlate strongly with topography, so focusing on the “setting” category for each component’s description is recommended. If the setting details alone don’t allow you to confidently determine your soil, the “properties and qualities” category under each component’s description would be the next best place to look. The goal is to find the component that has both a setting and soil characteristics that best match the point on your property that you are interested in. If that area on your property is rather large and not uniform, there is a high probability that multiple soils will exist in that area, especially if the map unit is a complex.

Q: How can soil information help me make management decisions?

A: Having a basic understanding of the distribution and characteristics of your soils can be extremely beneficial to you as a landowner. Knowledge of soil properties such as texture, drainage class, depth to a restrictive layer, and flooding or ponding frequency can influence management decisions including road and structure placement, as well as species selection and planting density strategies.

The summary information found in the map unit description provides a great overview of site and soil properties. However, the Web Soil Survey platform also contains hundreds of interpretations and thematic maps specifically designed to aid in the making of management decisions. Again, these tools are free and available to the public! The following steps will walk you through how to access and use these valuable tools.

Step 1: Define your AOI and access your soil map, as shown in steps 1-3 above. Click on the “Soil Data Explorer” tab. Then click either the “Suitabilities and Limitations for Use” or “Soil Reports” tab.

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Step 2: Both the “Land Management” and “Vegetative Productivity” categories have several interpretations concerning various aspects of forestry operations. Click the downward facing arrow for these categories and then click the downward facing arrow for any interpretation you would like to run. Look through the options and customize them to best apply to your situation. For example:

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Step 3: Once you have your options selected, click the “View Rating” button to see your customized interpretive map. Click the yellow “Legend” tab on the upper-left side of the map to see the map legend. Below the map will be tables containing more detailed results for the selected interpretation.

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Step 4: Explore the many reports and interpretations available under the “Suitabilities and Limitations for Use” and “Soil Reports” tabs. You may save the results of any report or interpretation by clicking the “Add to Shopping Cart” button located in the upper-right of the screen.  You can save numerous interpretations and reports by adding them to your cart. When you are finished, simply click on the “Shopping Cart (Free)” tab, review the table contents, and then click “Check Out” to download a PDF copy of your comprehensive report.

Max Ross, Soil Scientist, USDA Natural Resources Conservation Service, max.ross@wa.usda.gov