DIVERSIFYING LAND USE:
BLENDING FORESTRY AND AGRICULTURE
A proposal
submitted to
the Arkansas Forest Resources Center
Round 7
January 2000
Investigators:
Boris Zeide, Paul Francis, Richard Kluender,
and Richard Williams
Period: 36 months
Requested budget: $64,730
DIVERSIFYING LAND USE:
BLENDING FORESTRY AND AGRICULTURE
IMPACT STATEMENT
Issue
Forestry and agriculture are the two most common modes of land
management. Usually they are practiced
separately. Yet, combining these
practices is attractive for a variety of economic, environmental, and personal
reasons. While the returns from the forestry component materializes 15 or more
years after the planting of trees, the agricultural crops provide most of their
returns during the initial period, when growth of these components is at a
maximum. The diversity of land utilization can increase annual returns and by
spreading the risk over a number of crops makes cash flow more stable.
The agroforestry systems are beneficial for the environment. When rows of trees are planted along
contours, erosion is minimized. Cattle manure increases soil fertility and
activates many beneficial processes that are suppressed in dense stands. It is known that agroforestry systems are
inhabited by a greater number of bird and mammalian species than forest or
agricultural monocultures. Their microclimate is favorable to both plants and
animals and characterized by higher soil moisture, humidity and night-time
carbon dioxide levels, and lower evaporation that result in reduced respiration
rates. All these environmental advantages can be achieved without sacrificing
returns. These considerations justify
the search for the optimal combination of forestry and agricultural practices
and transferring this knowledge to farmers and foresters.
Action
To disseminate information about the advantages and methods of
agroforestry, we are planning to develop a guide that will help nonindustrial
private landowners to combine profitability and environmental benefits beyond
those found in simpler agricultural and forestry ecosystems. At the same time, we will continue
monitoring the agroforestry study established three years ago in Hope. Records of all activities and accompanying
costs and returns will be maintained.
Seasonal forage production, its quality, species composition, annual
biomass and elemental composition will be monitored.
Using our experience and all available information about agroforestry,
this project will contribute to the education of nonindustrial private
landowners, foresters, and extension agents.
We are planning to conduct regular workshops and tours on the study
area, arrange field trips for students and relevant conferences, and organize
other outreach activities.
Impact
This project will produce a number of
interconnected educational, technical, and scientific results. As compared with growing trees or cattle
separately, the advantages of agroforestry can raise income of farmers by
15-20%. By employing no-till practices,
decreasing erosion, and diversifying land use, the recommended activities
summarized in the guide will promote sustainable land management.
DIVERSIFYING LAND USE:
BLENDING FORESTRY AND AGRICULTURE
INTRODUCTION
Sustainable management on private lands can be made more profitable,
diverse, and attractive to landowners by combining the two most common uses of
land: forestry and agriculture. The
proposed project will benefit from our forestry and agroforestry experience. We have been recipients of the USDA NRICGP
grant No. 97-35108-5126 "Design of an agroforestry system with structured
tree clusters," which expires in November 2000. This grant has allowed us to establish a long-term study in Hope
and evaluate various layouts, distances between crop and nurse trees, forage
composition, pruning levels, and other forestry and agricultural options. The knowledge we have gained from this
multidisciplinary study provides a foundation that can be used for education of
landowners, integration of accumulated results, and furthering original
research in diverse and environmentally benign land management.
OBJECTIVES
1.
Summarize the best agroforestry practices in the form of a management
guide that will combine three key management components: growth information;
schedule of recommended operations; and costs and returns of each.
2.
Apply the scheduled management practices (hay harvesting, grazing,
thinning and pruning of trees) and continue monitoring of the economics and ecological
impacts of the established agroforestry systems.
3.
Use the results of monitoring in adaptive management and modify the
original designs on the basis of that feedback.
4.
Organize systematic technology transfer of the obtained results.
JUSTIFICATION
The coexistence of trees, forage, and livestock is natural and can be
mutually beneficial for several biological and managerial reasons. Root systems of established pines are deeper
than those of forage species. This fact
minimizes (though does not exclude) competition for soil nutrients and moisture
between pines and forage species.
During the early years of growth, crop trees occupy a small percentage
of the land. The remaining land is
covered by competing vegetation, which often severely retards pine growth.
Livestock grazing reduces competition between trees and shrubs. As a result,
grazing can substantially increase diameter and height growth of coniferous
species. One tenth of the trees
that we plant in a regular plantation provides at the end of rotation about
three quarters of all discounted returns.
In our study, we have planted these crop trees (loblolly pine, Pinus
taeda L., 50 per acre) surrounded by nurse trees (shortleaf pine, Pinus
echinata L.). The area between rows of tree clusters is utilized for forage
and beef production. Another reason for
increased growth is natural (manure) and artificial fertilizers applied near
the trees. In their turn, trees provide
shade and wind shelter for cattle.
The diversity of land utilization can increase annual returns and by
spreading the risk over a number of crops makes cash flow more stable. While the returns from the forestry
component will materialize 15-25 years after the planting of the crop trees,
the agricultural component will provide most of their returns during the
initial period, when growth of these components is at a maximum. As compared
with growing trees or cattle separately, these advantages can raise income of
farmers by 15-20%.
The agroforestry systems that we test provide environmental benefits.
When tree rows are planted along contours, erosion is minimized. Cattle manure
increases soil fertility and activates many beneficial processes that are
suppressed in dense forest monocultures. Agroforestry systems are more diverse
then either of the components. It is known that they are inhabited by a greater
number of bird and mammalian species. Their microclimate is favorable to both
plants and animals and characterized by higher soil moisture, humidity and night-time
carbon dioxide levels, and lower evaporation that result in reduced respiration
rates. All these environmental advantages can be achieved without sacrificing
returns.
Usually agroforestry designs call for planting trees of the same
species and age in rows with equal distances between trees. There have been attempts to plant trees in
clusters, within which trees are spaced uniformly. Our design implements planting two kinds of trees (crop and nurse
trees) and using different distances between them. On the study at Hope we test three types of structured rows, four
within-row distances, three thinning intensities, and three levels of pruning
for two agroforestry systems (improved agro-silvicultural system and the
agro-silvo-pastoral system) in three replications. Along with these technical parameters, this study intends to
optimize economic, ecological, and social benefits. Among social advantages of agroforestry is that it fits the human
life cycle. As farmers become older, they prefer less strenuous activities such
as timber management. If a farmer switches to agroforestry in his middle years,
then this transition will occur naturally.
The USDA grant that allowed us to establish this study ends in November
2000. The grant does not cover knowledge
diffusion and education, which is the Round 7 theme, nor plot management beyond
that date (scheduled treatments, soil analysis, tree inventories, hay
harvesting, grazing, and others). This
proposal will be focused on these areas.
APPROACH
AND METHODS
By stressing technology transfer, this project complements the USDA
grant. We are planning a variety of
educational methods: development of a management guide that summarizes the best
agroforestry practices, workshops and tours on the study area, field trips for
students and relevant conferences, and other outreach activities. At the same time, we are going to continue
to study maintenance, data analysis, and presenting the results in professional
publications and meetings.
The management guide we propose to develop will present the existing
agroforestry knowledge, including that obtained in our study, as a practical
step-by step chart of management practices.
This guide will allow landowners to:
- utilize the land more productively and sustainably;
- increase annual returns;
- make cash flow more stable and secure by spreading the risk over a
number of crops;
- gradually reduce management load as fits the human life cycle.
We will continue to implement the scheduled management practices and
monitor the economic and ecological impacts of the established agroforestry
systems. To prevent animals from damaging young trees in the treatment which
includes beef production, until pines reach the height of 3 m, the land is used
for forage production with no grazing included. Afterwards, cattle (preferably
unbred, because pine straw is somewhat toxic to unborn calves in pregnant cows)
will be allowed to graze.
Height and diameter of all trees will be measured during the dormant
period every year up to the age of 16 years and, when their growth slows down,
every three years thereafter. Records of all activities and accompanying costs
and returns will be maintained. During
the first five growing seasons (from February through September) and contingent
upon funding thereafter, the amount of forage production, its quality, species
and elemental composition will be measured between hay harvests using micro-plots (4 by 4 feet).
The distance of the micro-plots from trees will be recorded to document the
effect of shading. Total annual biomass production will be computed after every
season. These data will be used to adjust cattle stocking rates and provide
input to calculate the total productivity for each treatment. Cattle production
will be determined from weight gains.
Forage production during the grazing season will be determined using 4
by 4 feet exclosure cages placed at intervals from the trees for shading
documentation.
Comparison of investment alternatives related to the agroforestry
alternatives will be performed in a number of different ways. Present net worth (PNW) is the most commonly
recognized method. Normally, PNW values
are computed by analyzing the stream of discounted cash flows that are expected
to occur within the life of the investment.
Two different types of investments are considered in this study:
agricultural returns from beef, hay and forage, and a forest-based investment
from pine pulpwood and sawlogs. Using
the results of monitoring, we may modify the original designs.
Investment valuation of agricultural scenarios will be done as follows:
net annual income streams are evaluated on a PNW basis for a defined period
of time. In dynamic scenarios, when periodic changes are made in the
production base, such as crop rotation, or phasing out one crop in favor of
another, calculations are more difficult, but still relatively
straightforward. PNW values can be
easily converted to equivalent annual income values.
Education and technology transfer
will be implemented using a variety of methods. We are planning to:
- conduct regular workshops and tours on the
study area for nonindustrial private landowners, foresters, and extension
agents;
- maintain a mailing list of forestry,
agricultural, and conservation state and federal agencies as well as
non-government organizations (such as the Nature Conservancy and Arkansas Land
and Farm Development Corp.) and periodically inform them about the progress of
our agroforestry study;
- arrange field trips for students and relevant
conferences and other outreach activities;
- write papers for professional journals and
conferences;
- update the agroforestry management guide
upon receiving new results.
EXPECTED
RESULTS
This project will produce a number of interconnected educational,
technical, and scientific results. On
the basis of the established agroforestry study and other available
information, we will develop a management guide that will help nonindustrial
private landowners to combine profitability and environmental benefits beyond
those found in simpler agricultural and forestry ecosystems. By employing no-till practices, decreasing
erosion, and diversifying land use, the recommended management activities will
promote sustainable land management.
By its nature, agroforestry studies require long-term observations.
This project will continue maintenance of the Hope study and monitoring of
economics and ecological impacts. To make the expected results portable to
other sites, we will try to formulate them in relative terms with wider
applicability. For example, along with recommending to thin surrounding trees
at, say, age 14, we would also indicate that this event is to be scheduled when
diameter increment of core trees drops below 90% of the increment of open-grown
trees.
As a result of our educational efforts, we expect that agroforestry
will soon become as popular as traditional forestry and agriculture.
RESPONSIBILITIES
Zeide - design the structure of the
management guide; establish relationships between growth and its factors such
as age, stand density, and overall coordination of the project.
Francis - estimate the amount of forage
production, its quality, species and elemental composition. He will adjust cattle stocking rates and
provide input to calculate the total productivity for each treatment.
Kluender - assess compounded cost and return
and link variables required for economic analysis.
Williams - develop the Center's leafsheets
for private landowners and unite them in the management guide, organize
workshops and seminars for forestry professionals and private landowners.
CENTER=S GOALS/OBJECTIVES
Given its significance to forest management and environmental
sustainability, this project addresses practically all Goals/Objectives of the
Arkansas Forest Resources Center, including education. The project is
particularly relevant to Objectives 2.1 and 2.2 dealing with productivity and
sustainability of Arkansas forests and their management.
BUDGET
Position Per
year, $ Period Total, $
Two-year graduate assistantship 22,000
fringe benefits (0.5%), tuition (2,520), fees
(300) 2,930
Co-investigators 20,000
(Time, computer equipment, software, etc.)
Study maintenance 12,000
Travel 3,600
Publications 4,200
(Center's leafsheet publications, journal articles, AES reports)
Total 64,730
