AGROFORESTRY

IN THE

UNITED STATES

RESEARCH AND TECHNOLOGY TRANSFER

NEEDS FOR THE NEXT MILLENNIUM

ASSOCIATION FOR TEMPERATE AGROFORESTRY

Fall 2000

AFTA
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AGROFORESTRY

IN THE

UNITED STATES

RESEARCH AND TECHNOLOGY TRANSFER

NEEDS FOR THE NEXT MILLENNIUM

THE ASSOCIATION FOR TEMPERATE AGROFORESTRY

COLUMBIA, MISSOURI

FALL 2000

Funding for this project was provided by the USDA National Agroforestry Center.

Photos courtesy of the USDA.
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Formed in 1991, the Association for Temperate Agroforestry Inc. (AFTA) is a private, nonprofit organization. The mission of AFTA is to promote the wider adoption of agroforestry by

landowners in temperate regions of North America. Agroforestry practices combine trees and

shrubs with crops and/or livestock to increase and diversify farm and forest production while

conserving natural resources. AFTA pursues its mission through activities such as networking,

information exchange, public education, and policy development. These include 1) the

publication of a quarterly newsletter, The Temperate Agroforester, 2) co-sponsorship of the

biennial North American Agroforestry Conference series (begun in 1989), 3) preparation of

reports on agroforestry development and policy, and 4) serving as a liaison with regional

agroforestry groups.

This report builds upon the 1997 AFTA report - The Status, Opportunities, and Needs for

Agroforestry in the United States. The purpose of this report is to identify high priority research

questions and technology transfer needs for the five major agroforestry practice areas: 1) alley

cropping, 2) forest farming, 3) silvopasture, 4) riparian forest buffers, and 

5) windbreaks.

Experts for each practice area drafted sections of this report. The report was then sent to AFTA

members for review and comment. The final report reflects a consensus on high priority

research questions and technology transfer needs by the AFTA membership.

To request copies of this report or learn more about the Association for Temperate Agroforestry,

please write AFTA, 203 ABNR Building, University of Missouri, Columbia, MO 65211, or

email afta@missouri.edu. Please visit our website at www.missouri.edu/~afta.

Agroforestry in the U.S. is defined as:

Intensive land-use management that optimizes the benefits (physical, biological, ecological,

economic, and/or social) from biophysical interactions created when trees and/or shrubs are

deliberately combined with crops and/or livestock. 
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TABLE OF CONTENTS AFTA STRATEGIC DIRECTION

TABLE OF

CONTENTS

Introduction . . . . . . . . . . . . . . . . . . . . . . . . .1

Alley Cropping . . . . . . . . . . . . . . . . . . . . . .5

Forest Farming . . . . . . . . . . . . . . . . . . . . . .9

Riparian Forest Buffers . . . . . . . . . . . . . . .13

Silvopasture . . . . . . . . . . . . . . . . . . . . . . . .17

Windbreaks . . . . . . . . . . . . . . . . . . . . . . . .21
AFTA STRATEGIC DIRECTION
t has happened slowly but surely. Over the

last two or three decades dramatic

adjustments to farmland management and

ownership have changed the face of the

American "farmscape." One alarming change is

that a significant portion of prime farmland and

ranchland is being lost to development (e.g.,

converted to home sites, factories, roads, and

shopping centers). In the U.S. an estimated fifty

acres of farmland is now lost every hour of

every day to development pressures. Similarly,

forest cover in the U.S. has started to decline

after remaining essentially constant since the

1920s. As the U.S. population continues to

increase by three million each year, forestry and

agriculture will both face the problem of

meeting an increasing demand for goods, as

well as for an expanding array of services, such

as clean water, recreation, and wildlife habitat.

More importantly, society will have to meet its

needs with a fixed or shrinking land base.

Agriculture and forestry share many goals and

over the centuries they have provided the

strategic foundation for our country. Together

they comprise more than 75 percent of the land

use in the U.S. Too often there is a tendency to

treat agriculture and forestry separately when

addressing natural resource concerns. Yet, a

high proportion of the watersheds and

landscapes in this country are an interwoven

mosaic of both uses. Rural communities often

depend on both agriculture and forestry to

remain economically viable. Solutions are

needed that build from a comprehensive, alllands approach. Otherwise, it is like trying to

make a patchwork quilt without bothering to

sew the pieces together -- everything comes

unraveled.

Technology can provide some productivity

gains as improved crops become available

through biotechnology and genetic engineering,

but the heavy reliance on fertilizers and

pesticides already is manifesting its own nottoo-subtle impact on the environment.

Likewise, consumers and producers are engaged

in a lively debate on food safety and

environmental issues related to the production

and consumption of genetically modified crops.

In the future, agriculture may be able to produce

sufficient food to meet the world's demand but

production costs will rise and so too will the

cost of food and the potential for negative

impacts to the environment.

Agriculture Needs Agroforestry

When the USDA National Commission on

Small Farms Report was issued in January

1998, it listed several recommendations on

agroforestry and concluded that.... "USDA

extension, conservation, and forestry services

should make greater efforts to promote and

support agroforestry as part of an economic and

ecological strategy for a healthy agriculture."

Today, many farmers and ranchers are

struggling to make a livelihood on small

acreage farms. They often have limited financial

means and are seeking ways to maximize their

income per acre, while keeping their

requirement for purchased inputs low.

Production systems need to become more

diverse. New crops and new production

methods need to be embraced. Cost-effective

alternatives that can meet environmental goals

and increase profits need to be available to

producers.

A more diversified agricultural sector means

producers will need to select from a broad

portfolio of management practices; practices

that include science-based agroforestry

technologies. Most agroforestry practices are

designed to be readily integrated into existing

farm operations. In many instances, the

adoption of one or several agroforestry practices

can be the difference between profitability and

economic loss. 

I

ULTIMATELY THE CHALLENGE WILL BE TO FIND WAYS TO SUSTAIN THE PROVISION OF

GOODS AND SERVICES THAT SOCIETY DERIVES FROM FORESTS AND AGRICULTURE IN

WAYS “...THAT MEET THE NEEDS OF THE PRESENT WITHOUT COMPROMISING THE

ABILITY OF FUTURE GENERATIONS TO MEET THEIR OWN NEEDS.”

INTRODUCTION AFTA STRATEGIC

DIRECTION

1
Forestry Needs Agroforestry

The U.S. made a commitment to sustainable

forest management when it signed the Santiago

Declaration in 1995. However, there are places

in the U.S. that are already experiencing

difficulty meeting society’s expectations for

some forest-derived benefits. For example, in

many areas land use fragmentation patterns

across the landscape have resulted in the

reduction of many plant and animal species that

rely on forest habitat. In other regions there are

projections of inadequate wood supply.

Insufficient water quality and aquatic habitat are

issues that now affect most regions. 

If society's needs and aspirations for forestderived goods, services, and amenities truely are

to be met, we must find ways of augmenting

traditional forestry by gleaning some portion of

these benefits from agricultural lands. For

example:

• Windbreaks can provide corridors across 

agricultural lands to connect forest fragments 

and increase wildlife benefits, while protecting 

soils, crops, and livestock, conserving energy, 

and producing commercially valuable 

products.

• Riparian forest buffers on farms and ranches 

can protect surface waters from sediments, 

nutrients, and contaminants, while enhancing 

aquatic habitats, producing marketable

products, and sequestering carbon.

• Fast-growing hybrid poplar trees grown on 

farmlands can treat agricultural waste and 

provide income for farmers, while helping to 

meet the demand for wood fiber and energy.

• Farm woodlots can be used to grow specialty 

products such as ginseng or mushrooms under 

a modified forest canopy, thereby encouraging 

timber stand improvement practices. 

• Grazing/timber systems allow farmers to 

generate an annual income from grazing 

livestock under thinned forest stands while 

producing high quality sawlogs.

A COMPREHENSIVE APPROACH IS NEEDED

TO INCREASE THE INVESTMENT

IN DEVELOPING AND IMPLEMENTING

AGROFORESTRY PRACTICES

IN THE U.S.

THIS NEEDS TO OCCUR THROUGH AN EXPANSION

OF EXISTING STATE AND FEDERAL AGENCY PROGRAMS,

AN INCREASED USE OF LANDOWNER ASSISTANCE PROGRAMS, AND

BY EXPLICITLY INCLUDING AGROFORESTRY

IN COMPETITIVE RESEARCH GRANT AND EXTENSION PROGRAMS.

2 AFTA STRATEGIC

DIRECTION INTRODUCTION
Agroforestry is Relevant to Many Issues

With more than eighty percent of Americans now living in urban or suburban environments, it

has become increasingly important that the public understand that much of what it values is

derived from agriculture and forestry. People need to understand that clean water does not just

happen; that the food and fiber they consume and the wastes they generate have associated

consequences and responsibilities. 

There is no shortage of issues that agroforestry can help resolve. Although many resource

professionals and landowners don't yet understand the full benefits of adding agroforestry

practices to their land management portfolio, many are beginning to investigate the possibilities.

Most farmers, ranchers, and communities cannot afford to plant trees or shrubs simply because

it's the right thing to do. It's hard to be virtuous when you're in a daily struggle to make ends

meet. But once a landowner in an area implements an agroforestry practice that successfully

solves a problem, agroforestry often begins to "sell itself" to his or her neighbors.

Agroforestry practices are grouped into five categories: 1) alley cropping, 2) forest farming, 3)

silvopasture, 4) riparian buffers, and 5) windbreaks. This document describes agroforestry

practices within each of these categories and lists associated high priority research questions and

technology transfer needs. 

Overarching Needs

There are some common needs that apply to all agroforestry practices. More regional workshops

and field demonstration projects can help illustrate both the logistics and the economics of an

agroforestry practice to resource conservation professionals and landowners. The generation of

educational materials, such as videos and “how-to” manuals, that provide specific guidance on how

to design, install, and manage agroforestry practices, along with innovative extension/outreach

programs, will facilitate more local adoption. The networking and integration among resource

agencies at the national, state, and local levels needs to increase.

Since agroforestry is a hybridization of agriculture and forestry conservation and production

technologies, landowners need to be able to evaluate the economic performance of an agroforestry

practice against traditional forestry and agricultural cropping alternatives. In most instances there

remains a need to better characterize the economic cost for establishment and maintenance of an

agroforestry practice and its economic return. This must include considerations of financial risk and

operational complexity. Region-specific economic analyses are needed that present information in

ways that natural resource professionals and landowners can understand. In many areas landowners

are seeking advice on how to form cooperatives to harvest and market new products.

INTRODUCTION AFTA STRATEGIC

DIRECTION

3
4 AFTA STRATEGIC

DIRECTION

Agroforestry practices have been shown to

provide benefits in many settings:

• Carbon Storage - 

Sequesters large amounts of carbon in trees and shrubs across a large landbase.

• Pest Management -

Provides habitat for beneficial insects and birds. Presents a physical barrier that interrupts 

pest cycles.

• Soil Conservation - 

Reduces loss of soil organic matter, nutrients, and soil particles.

• Streams and Lakes - 

Protects water quality by intercepting sediments and agricultural chemicals. Reduces 

streambank erosion and improves aquatic habitat.

• Water Conservation - 

Reduces evaporation and plant transpiration, beneficially distributes snowmelt, and 

protects riparian zones from agricultural runoff.

• Wildlife Habitat - 

Provides food, cover, nesting sites, and travel lanes.

• Economic Benefit -

Provides income from trees and their products, while allowing for annual income from 

crop and livestock production. Improves crop yield and quality.

• Livestock - 

Protects livestock from harsh climate, improves animal health, and lowers feed costs. 

Provides annual income from grazing/timber systems. Moderates noise and odor from 

animal operations.

• Aesthetics -

Provides plant diversity, wildlife habitat, and recreational corridors.

• Energy Conservation - 

Reduces energy costs associated with farm operations.
wo incomes in the space of one...

Making a living from year to year off

an annual crop is fraught with

uncertainty. Success depends on

weather conditions and favorable markets at

harvest. Alley cropping systems provide a way

to lower risk by diversifying production. In

alley cropping an agricultural crop is grown

simultaneously with a long-term tree crop to

provide annual income while the tree crop

matures. Traditionally, fine quality hardwoods

such as walnut, pecan, and oak have been

preferred species, as they can be managed to

produce high-value lumber or veneer logs. More

recently, fast-growing hybrid poplar trees are

being grown for sawtimber in 15-20 year

rotations. When nut-bearing trees are used, they

can provide an intermediate product for sale. In

addition to improving annual cash flow, these

systems also protect annual crops from wind,

reduce soil erosion, and provide wildlife habitat.

Most row, grain, and forage crops, as well as

specialty crops, such as catnip or St. John's

Wort, have been shown to grow well in an alley

cropping system.

ALLEY CROPPING

T

ALLEY

CROPPING AFTA STRATEGIC

DIRECTION

5
ALLEY CROPPING - The level of investment in research on alley cropping

must increase. More information is needed to provide the scientific basis for designing

practices that can meet an expanding set of landowner and societal objectives. AFTA has

identified the following high priority research questions:

RESEARCH QUESTIONS

What crop rotation systems and tree and shrub species are compatible in various

regions of the country?

What is the combined yield of different tree, shrub, and crop combinations,

especially conventional crops?

What are the optimal row spacings for different tree, shrub, and crop

combinations?

How can weeds be controlled, particularly at the interface between tree rows

and crops?

Which insects and diseases are significant problems and can beneficial insects

be used in an integrated pest management system?

6 AFTA STRATEGIC

DIRECTION

ALLEY

CROPPING
ALLEY

CROPPING AFTA STRATEGIC

DIRECTION

7

ALLEY CROPPING - The level of investment in technology transfer on alley

cropping must increase. Increased technology transfer efforts should focus on packaging

completed, but scattered, research results to facilitate their use by resource professionals

and landowners. AFTA has identified the following high priority information needs:

TECHNOLOGY TRANSFER NEEDS

Region-specific technical information that provides suitability ratings for tree

and shrub species and compatible crops.

Operational guidelines for managing trees, shrubs, and crops in various alley

cropping arrangements.

Guidelines for tree establishment by region.

Information on cost-share programs for establishment and maintenance.

Educational information on marketing strategies and how to establish

cooperatives.

Information on different manual and machine-assisted pruning methods.

Regional economic data on common tree, shrub, and crop combinations.

Farmer-friendly financial analysis models that compare the costs and benefits of

various alley cropping practices over time.

Information on the availability of plant material.
8 AFTA STRATEGIC DIRECTION
ade in the shade... Many farmers

who own woodlots are finding they

can make money in the shade.

Many high-value specialty crops

are now being cultivated under the protection of

a forest canopy that has been modified to

provide the appropriate microclimate and light

conditions. Meanwhile, the timber stand

improvement activities that are carried out to

develop the appropriate understory conditions,

like thinning less desirable stems and pruning

lower branches on the eventual “crop” trees, can

result in the production of clean, knot-free wood

of higher value as a long-term economic

strategy. Shade tolerant crops such as ginseng,

goldenseal, shiitake mushrooms, and decorative

ferns are being grown and sold for medicinal,

culinary, or ornamental uses.

FOREST

FARMING AFTA STRATEGIC

DIRECTION

9

FOREST FARMING

M
10 AFTA STRATEGIC

DIRECTION

FOREST

FARMING

FOREST FARMING - The level of investment in research on forest farming must

increase. More information is needed to provide the scientific basis for designing efficient

production practices. AFTA has identified the following high priority research questions:

RESEARCH QUESTIONS

What stocking levels are appropriate for various tree species to regulate

understory shade and microclimate for the production of floral greens,

mushrooms, ginseng, and other specialty crops? 

Which non-timber forest products have the economic potential to be grown under

a forest canopy, and what are their growth requirements?

What are the start-up and operating costs for producing various understory crops? 

How compatible are existing forest/woodlot management strategies with the

production of understory crops?

What are the effects of shade levels on valued-properties of understory crops, for

example the concentration of chemically active compounds?

Will different genotypes of understory crop species provide production gains?

How can woody plants that produce specialty forest products be integrated into

other agroforestry practices, like windbreaks and riparian forest buffers?

How do the economics of forest farming compare to those of traditional forestry?

What are the characteristics of current and evolving markets for the major

specialty forest products?
FOREST

FARMING AFTA STRATEGIC

DIRECTION 11

FOREST FARMING - The level of investment in technology transfer on forest

farming must increase. Increased technology transfer efforts should be focused on

packaging completed, but scattered, research results to facilitate their use by resource

professionals and landowners. AFTA has identified the following high priority

information needs:

TECHNOLOGY TRANSFER NEEDS

Information on region-specific marketing opportunities for understory species at

both wholesale and retail levels.

Information on buyer standards and specifications for understory crops.

Region-specific production enterprise budgets for common understory crops.

Understory cropping practices that are compatible with various forest

management practices, such as timber stand improvement or shelterwood cuts.

Handbook on the production, marketing, and sale of specialty forest products

with specific information on species and improved cultivars.

Information on sources of agroforestry plant materials, such as fodder-producing

tree varieties, shade-tolerant fruit species, medicinal plants, decorative flowers,

bioremediators, and handcrafts.

Financial analysis models of costs and returns to landowners from various forest

farming practices.
12 AFTA STRATEGIC DIRECTION
ater matters...Many of the waters

in the United States are polluted to

the extent that they can no longer

be safely used to supply drinking

water, for swimming and other recreation

opportunities, or to provide edible fish. Much

of the loss of water quality has been shown to

be a result of non-point source pollution from

agricultural activities. Practices like cropping

and grazing often occur up to the edges of

streams, lakes, ponds, and wetlands. The result

is a loss of aquatic habitat and high levels of

sediment and chemical inputs which lower

water quality. Forested riparian buffer practices

consisting of grasses, shrubs, and trees have

been shown to be an effective strategy for

improving water quality by intercepting

sediments, filtering excess nutrients, and

degrading pesticides. They also can stabilize

streambanks, protect floodplains, enhance

aquatic and terrestrial habitats, and provide

landowners with harvestable products.

RIPARIAN FOREST

BUFFERS

W

RIPARIAN

FOREST

BUFFERS AFTA STRATEGIC

DIRECTION 13
14 AFTA STRATEGIC

DIRECTION

RIPARIAN

FOREST

BUFFERS

RIPARIAN FOREST BUFFERS - The level of investment in research on

riparian forest buffers must increase. More information is needed to provide the scientific

basis for designing buffers that can meet an expanding set of landowner and societal

objectives. AFTA has identified the following high priority research questions:

RESEARCH QUESTIONS

What are the above- and below-ground carbon dynamics of riparian buffers? 

How do buffer design criteria, such as width, age, vegetation type, and

management, influence their ability to process different contaminants, such as

sediments, nutrients, and pesticides?

How do landscape parameters, such as site characteristics, land uses, hydrology,

and topography, influence riparian buffer functions related to water quality, bank

stabilization, and flood protection?

What management is needed to maintain the intended buffer functions over time?

How can information at the plot/field/farm level be scaled to the watershed level?

What are the establishment and maintenance costs associated with various buffer

designs over time?

How does the effectiveness of riparian buffers vary with season and different

levels of contaminant loading?

What is the potential of various riparian forest buffers to provide wildlife habitat?

What tree and shrub species can be incorporated into riparian forest buffers to

produce income-generating specialty forest products?
RIPARIAN

FOREST

BUFFERS AFTA STRATEGIC

DIRECTION 15

RIPARIAN FOREST BUFFERS - The level of investment in technology

transfer on riparian forest buffers must increase. Increased technology transfer efforts

should be focused on packaging completed, but scattered, research results to facilitate

their use by resource professionals and landowners. AFTA has identified the following

high priority information needs:

TECHNOLOGY TRANSFER NEEDS

Management guidelines for riparian forest buffers that allow for the economic

usage or harvest of trees that are not adjacent to the water.

An expanded USDA Conservation Reserve Program that provides cost-share

and land rental payments that include streambank bioengineering and

constructed wetlands. 

Educational materials on how to design riparian forest buffers that

simultaneously meet conservation objectives along with providing opportunities

for commodity production practices.

Computer simulation models that operate at the regional level to gauge the

effectiveness of different buffer designs and placements.

Tools to identify and predict pollutant pathways in landscapes to identify the

most efficient design and placement of riparian buffers in the landscape.

Decision support tools to help determine on-farm financial performance of

riparian forest buffers. 

Listing and sources for tree, shrub, and understory species and cultivars with

potential economic value.
16 AFTA STRATEGIC DIRECTION
rees grow old but so do farmers...

Many farmers who own conifer

woodlots simply wait for the trees to

grow bigger and then take whatever

price they can get for a once in a lifetime

harvest. Unfortunately, the price often is low

due to the lack of timber stand improvement

activity throughout the rotation. Thinning less

desirable stems and pruning lower branches on

the eventual "crop" trees could have resulted in

the production of clear, knot-free wood of

higher value. Fortunately, agroforestry

silvopasture practices are conducive to

promoting forest management, while generating

forage production in the understory that is

suitable for livestock grazing. 

Recent research has shown that many cool- and

warm-season grasses and legumes yield high

levels of quality forage when grown under as

much as fifty percent shade. This knowledge is

being used to design integrated timber/grazing

practices in conifer stands that allow high value

sawlogs to be grown as a long-term product,

while on the same acre, an annual income can

be generated from grazing livestock.

Silvopasture field studies have shown that the

"crop" trees continue to grow well, while the

level of forage production is similar to that of an

open pasture.

Although it takes longer, it is also possible to

establish tree seedlings in an open pasture or

crop field. Trees must be protected from grass

competition and animal grazing until they reach

adequate size. In the meantime, the trees

displace very little land from grazing or crop

production during the initial years of

establishment.

Research has also begun to evaluate the

potential for silvopature with hardwood species. 

SILVOPASTURE AFTA STRATEGIC

DIRECTION 17

SILVOPASTURE

T
18 AFTA STRATEGIC

DIRECTION

SILVOPASTURE

SILVOPASTURE - The level of investment in research on silvopasture practices

must increase. More information is needed to provide the scientific basis for designing

silvopasture practices that can meet an expanding set of landowner and societal objectives.

AFTA has identified the following high priority research questions:

RESEARCH QUESTIONS

What are the effects of wide spacing, pruning, and fertilization on the production

and quality of wood and forage?

What is the efficiency of multi-row and multi-species tree planting vs. single-row

and single-species plantings for converting open areas to silvopastures?

How do the tree and forage components interact to compete for light, water, and

nutrients?

Can supplemental products be produced in silvopastures, such as pine straw?

How compatible are other conifer cover types, such as ponderosa pine and

Douglas-fir to silvopasture management?

How compatible is silvopasture with hardwood tree species?

What are the yield and quality of cool- and warm-season forages as affected by

various management regimes under tree shade?

What are the forage preferences of cattle, goats, and sheep in a silvopasture

practice, and what is their compatibility with the trees?

How do cultural practices such as mowing, herbicide, and cultivation affect the

establishment and early growth of tree seedlings planted into existing pasture?

Can other commercially viable specialty products be produced in silvopasture

systems to enhance biological and economic diversity?
SILVOPASTURE AFTA STRATEGIC

DIRECTION 19

SILVOPASTURE - The level of investment in technology transfer on silvopasture

must increase. Increased technology transfer efforts should be focused on packaging

completed, but scattered, research results to facilitate their use by resource professionals

and landowners. AFTA has identified the following high priority information needs:

TECHNOLOGY TRANSFER NEEDS

Region-specific production and economic budgets for silvopastoral enterprises.

Guidelines for converting coniferous farm woodlots into silvopastures.

Guidelines for converting alley cropping enterprises into silvopasture.

Information on equipment, markets, and economics of on-farm timber

processing.

Information on compatible combinations of tree and forage species.

Cost-effective methods of protecting newly planted tree seedlings from livestock

damage. 

Economic analysis models that are operational at the regional scale (e.g.

Agroforestry Estate Model).

Information on silvopasture benefits for livestock.

Information on benefits/problems of various types of livestock and tree

combinations.
20 AFTA STRATEGIC DIRECTION
ind happens.... In the summer, hot

dry winds deplete water resources

by increasing surface evaporation

and elevating plant transpiration

rates. Exposed soil can become subject to wind

erosion and unprotected crops can be stressed.

Odors associated with livestock can be

transported long distances, as can spray drift

from the application of agricultural chemicals

and dust from farming operations. In the

winter, the chilling effects of wind and drifting

snow often cause hardships to farm families and

their livestock, as well as to rural communities.

The concept behind windbreaks is not new.

They are also referred to as "shelterbelts" and

have been used extensively in the United States

since the "dust bowl" era of the 1930s and now

comprise about 1.5 million acres. A

windbreak's major function is to reduce wind

speed. Therefore, a windbreak can be defined

as any barrier that reduces troublesome winds

by creating a wind shadow to the leeward

(downwind) side. An agroforestry windbreak is

one that utilizes single or multiple rows of trees

and/or shrubs that are integrated into

agricultural systems.

What is new is the expanding array of issues

windbreaks are being asked to address. While

an extensive body of knowledge and technical

guidelines has been developed, past efforts have

been concentrated on the use of field

windbreaks to prevent soil erosion, protect crops

from drying winds, and deflect blowing snow.

Today, windbreaks are being used for a wide

variety of purposes.

WINDBREAKS

W

WINDBREAKS AFTA STRATEGIC

DIRECTION 21
22 AFTA STRATEGIC

DIRECTION

WINDBREAKS

WINDBREAKS - The level of investment in research on agroforestry windbreaks

must increase. More information is needed to provide the scientific basis for designing

windbreaks that can meet an expanding set of landowner and societal objectives. AFTA has

identified the following high priority research questions:

RESEARCH QUESTIONS

How does porosity relate to the effectiveness of windbreaks for achieving various

landowner objectives and how can porosity be conveniently measured.

How can older, deteriorated field and farmstead windbreaks be renovated in a

cost-effective manner?

How can woody species that produce specialty forest products be incorporated

into windbreaks to increase economic returns to landowners?

What are the benefits of windbreak protection for a large array of crops?

What is the economic value of reduced soil erosion?

How do windbreaks affect crop water-use, to include irrigation efficiency and

snow management?

Which design and management options provide the best direct economic return to

the landowner?

What are the benefits of various windbreak designs used for livestock and how

effective are they in mitigating odors and reducing dust?

Can short-rotation woody crops be effectively designed into windbreaks to

generate additional income while providing crop and livestock protection?

How effective are fast growing tree species, such as hybrid poplar, at treating

irrigation wastewater and wastes from animal feeding operations on-farm?

What is the potential of windbreaks to store carbon above- and below-ground at

the field level and nationally?
WINDBREAKS AFTA STRATEGIC

DIRECTION 23

WINDBREAKS - The level of investment in technology transfer on agroforestry

windbreaks must increase. Increased technology transfer efforts should be focused on

packaging completed, but scattered, research results to facilitate their use by resource

professionals and landowners. AFTA has identified the following high priority

information needs:

TECHNOLOGY TRANSFER NEEDS

Economic fact sheets using existing data for crop production in association with

windbreak practices.

Economic data on the influence of windbreaks on feed requirements, mortality

rates, and animal health for animal feeding operations.

Windbreak designs that maximize plant species diversity to reduce the negative

impact of insects, diseases, and weed infestations on windbreaks.

Educational materials to promote proper windbreak management and renovation

by the public.

Learning materials to better educate natural resource professionals and

university agricultural science and forestry students on windbreak technologies.

Informational tools about windbreak practices that optimize the production of

marketable specialty forest products to increase income for small farms.

Management and economic guidelines for harvesting timber or non-timber

products while maintaining windbreak functions.