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Agroforestry for Farms and Ranches
Agroforestry Technical Note No. 1, July 1, 1996
An introduction to using tree and shrub practices in sustained agricultural systems.
Agroforestry Defined
Agroforestry is the intentional growing of trees and shrubs
in combination with crops or forage. Agroforestry also includes
tree and shrub plantings on the farm or ranch that improve habitat
value or access by humans and wildlife, or that provide woody
plant products in addition to agricultural crops or forage. Agroforestry
is distinguished from traditional forestry by having the additional
aspect of a closely associated agricultural or forage crop.
Diverse Purposes of Agroforestry Systems
Properly designed agroforestry systems protect crops and forage,
increase their production, protect soil and water resources, conserve
energy, improve ecosystem "richness", create additional
wildlife habitat, and increase landscape diversity. They also
provide additional farm or ranch products: timber, pulpwood, firewood,
posts, fruit, nuts, and fodder to name a few. Agroforestry represents
a collection of multipurpose practices that are enduring and help
achieve a sustainable agriculture. These practices can form the
major part of a "Resource Management System" for a particular
field or treatment unit. The matrix below provides some examples
of how practices might be combined into agroforestry systems in
cropland and pasture/hay settings.
Potential Agriculture Problems |
Wind impacts (erosion, crop loss, inefficient water use) |
Water erosion |
Degraded or unbuffered stream/riparian areas |
Limited crop diversity (lack of tree/wood products integrated with agricultural crops) |
Fragmented wildlife habitat or low biodiversity of perennial plants |
Sustainable Agroforestry Systems (A + B + C) |
A. Principal Tree/Shrub Practices: |
Windbreak/ Shelterbelt Establishment |
Contour Buffer Strips (woody species)
Tree/Shrub Establishment |
Riparian Forest Buffer
Filter Strip (woody species) |
Alley Cropping
Multistory Cropping |
Tree/Shrub Establishment |
B. Principal Agronomic Practices - Cropland Settings |
Conservation Crop Rotation
Residue Management
Cross Wind Stripcropping
Herbaceous Wind Barrier
Irrigation Water Management |
Conservation Crop Rotation
Stripcropping, Contour
Contour Farming
Residue Management
Terrace |
Streambank and Shoreline Protection
Critical Area Planting
Use Exclusion
Nutrient and Waste Management |
Conservation Crop Rotation
Residue Management |
Conservation Crop Rotation
Residue Management
Use Exclusion |
C. Principal Grazing Management Practices - Pasture/Hay Settings |
Irrigation Water Management
Prescribed Grazing
Fencing |
Pasture and Hay Planting
Prescribed Grazing
Fencing |
Prescribed Grazing
Fencing
Pasture and Hay Planting
Nutrient/Waste Management |
Pasture and Hay Planting
Prescribed Grazing
Fencing |
Pasture and Hay Planting
Prescribed Grazing
Fencing |
Guidance on System Design
What practices work together? What are the design elements
used for an agroforestry system? Tables 1 and 2 provide an overview
of individual agroforestry systems to help answer these questions
and provide a link to the National Handbook of Conservation Practices
(NHCP) and the Field Office Technical Guide (FOTG). The NHCP and
FOTG are maintained by the USDA, Natural Resources Conservation
Service. Specific systems within a table may be found by referring
to the list below.
Table 1. Row-Types:
Table 2. Block-Types:
The NHCP establishes official names for all conservation practices
and sets national standards for each practice's design. The FOTG
further refines each practice standard for use in a particular
state. The agroforestry types listed in the tables are named by
the predominant tree/shrub practice in the System.
Planning Considerations for Systems
For a farmer or rancher to adopt an agroforestry system, he
or she must be both able and willing to incorporate rows or blocks
of trees and/or shrubs in individual fields or units. The landowner
must understand the new system, concur with its relative advantage
to the operation, and be able to incrementally install and maintain
the required practices. The landowner must also be aware of the
time it takes for the trees and shrubs to grow and their silvicultural
or management requirements. Interim systems to achieve objectives
may be necessary for the first 5 to 10 years while trees and shrubs
become functional. The use of equipment and chemicals (particularly
herbicides) may require a greater level of control to prevent
harm to crowns, stems and roots. For woody plants that will be
harvested or yield products, the landowner will most likely have
to acquire special marketing information and techniques. Properly
designed agroforestry systems offer many benefits to farmers,
ranchers and the public.
Some Definitions
Block-Types (Agroforestry System): Types of agroforestry
systems consisting of agronomic or forage practices with an integral
tree or shrub practice that is arranged in a block or rectangular
pattern (the width or short axis of the block typically greater
than 100 feet).
Row-Types (Agroforestry System): Types of agroforestry
systems consisting of agronomic or forage practices with an integral
tree or shrub practice that is arranged in a row-type or strip
pattern (the width of the individual strips typically less than
100 feet).
Density (windbreaks and row-type plantings): Density
refers to the percentage of the "background" scene that
is blocked from view when standing away from the planting and
looking perpendicular through it. "H" refers to the
expected height of the tallest tree or shrub row in the planting
at a specified or base age, usually 20 years in temperate climates
and 10 years in tropical areas. The term "5H," for example,
refers to the calculation of multiplying the constant, 5, times
the expected height at the base age.
Conservation Practice Standard (code numbers in parentheses)
The following table is based upon the National Handbook
of Conservation Practices (NHCP) page developed
by the NRCS staff at Fort Worth, Texas. Please consult this site
for additional conservation practices. While we will strive to
keep our version of the table as up-to-date as possible, consult
the Ft. Worth site if unable to access a particular practice from
our page.
Notices: Notices posted here are official documents that have been signed.
These Conservation Practice Standards require
Adobe Reader.
-
Access Control (AC) (472)
(PDF; 24 KB)
- Excluding animals, people
or vehicles from an area.
-
-
Alley
Cropping (AC) (311) (PDF; 27 KB)
- An agroforestry practice consisting of growing trees or shrubs in rows or corridors
with alleys of agronomic crops or forage between.
-
Conservation Crop Rotation (AC) (328)
(PDF; 11 KB) - Growing crops in a recurring sequence on the same field.
- Contour
Buffer Strips (AC) (332) (PDF; 57 KB)
- Plantings consisting of tree/shrub rows or strips of herbaceous vegetation on the
contour or cross-slope.
-
Contour Farming (AC) (330) (PDF; 37 KB)
- Farming sloping land
in such a way that preparing land, planting, and cultivating
are done on the contour. (This includes following established
grades of terraces or diversions.)
-
Cross Wind Ridges (AC)
(588) (PDF; 21 KB)
- Ridges formed by
tillage or planting and aligned across the prevailing wind erosion
direction.
-
Cross Wind Trap Strips (AC) (589C)
(PDF; 24 KB)
- Herbaceous
cover resistant to wind erosion, established in one or more strips
across the prevailing wind erosion direction.
-
Diversion (FT) (362) (PDF; 12 KB)
- A channel constructed across
the slope with a supporting ridge on the lower side.
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Fence (FT) (382) (PDF; 24 KB)
- Enclosing or dividing an area
of land with a suitable permanent structure that acts as a barrier
to livestock, big game, or people (does not include temporary
fences).
-
Filter Strip (AC) (393) (PDF; 43 KB)
- A strip or area of vegetation
for removing sediment, organic matter, and other pollutants from
runoff and waste water.
-
Grassed Waterway (AC) (412) (PDF; 42
KB)
- A natural or constructed
channel that is shaped or graded to required dimensions and established
in suitable conveyance for runoff.
-
Herbaceous Wind Barriers (FT)
(603) (PDF; 70 KB)
- Herbaceous
vegetation established in rows or narrow strips across the prevailing
wind direction.
-
Irrigation System (NO. AND AC), Trickle (441)
(PDF; 30 KB)
- A planned irrigation system in which all necessary facilities
are installed for efficiently applying water directly to the
root zone of plants by means of applicators (orifices, emitters,
porous tubing, perforated pipe) operated under low pressure.
The applicators can be placed on or below the surface of the
ground.
-
Irrigation Water Management (AC) (449)
(PDF; 27 KB)
- Determining
and controlling the rate, amount, and timing of irrigation water
in a planned and efficient manner.
-
Mulching (AC) (484) (PDF; 49 KB)
- Applying plant residues or
other suitable materials not produced on the site to the soil
surface. (Used for moisture conservation around newly planted
trees and shrubs.)
-
Multi-story Cropping (AC) (379) (PDF; 28 KB)
- An agroforestry practice
consisting of growing an overstory of trees or shrubs with an
understory of agronomic crops or forage.
-
Nutrient Management (AC) (590) (PDF; 40
KB)
- Managing the amount,
form, placement, and timing of applications of plant nutrients.
-
Pasture and Hay Planting (AC) (512)
(PDF; 70 KB)
- Establishing
and reestablishing long-term stands if adapted species of perennial,
biennial, or reseeding forage plants.
-
Pest Management (AC) (595) (PDF; 42 KB)
- Managing agricultural pest infestations
(including weeds, insects, and diseases) to reduce adverse effects
on plant growth, crop production, and environmental resources.
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Residue Management, Mulch Till (AC)
(345) (PDF; 64 KB)
- Managing
the amount, orientation and distribution of crop and other plant
residues on the soil surface year-round, while growing crops
where the entire field surface is tilled prior to planting.
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Residue Management, No-Till and Strip Till (AC) (329)
(PDF; 34 KB)
- Managing the amount, orientation and distribution of crop and
other plant residues on the soil surface year-round, while growing
crops in narrow slots or tilled strips in previously untilled
soil and residue.
-
Residue Management, Ridge Till (AC)
(346) (PDF; 56 KB)
- Managing
the amount, orientation and distribution of crop and other plant
residues on the soil surface year-round, while growing crops
on preformed ridges alternated with furrows protected by crop
residues.
-
Residue Management, Seasonal (AC) (344)
(PDF; 48 KB)
- Managing
the amount, orientation and distribution of crop and other plant
residues on the soil surface during part of the year, while growing
crops in a clean tilled seedbed.
-
Riparian Forest Buffer (AC) (391) (PDF;
26 KB)
- An area of trees
and/or shrubs located adjacent to and up-gradient from water
bodies.
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Streambank And Shoreline Protection (FT) (580)
(PDF; 27 KB)
- Using vegetation or structures to stabilize and protect banks
of streams, lakes, estuaries, or excavated channels against scour
and erosion.
-
Stripcropping (AC), Contour (585)
(PDF; 43 KB)
- Growing crops
in a systematic arrangement of strips or bands on the contour
to reduce water erosion. The crops are arranged so that a strip
of grass or close-growing crop is alternated with a strip of
clean-tilled crop or fallow or a strip if grass alternated with
a close-growing crop.
-
Terrace (FT) (600)
(PDF; 63 KB)
- An earth embankment, channel,
or a combination ridge and channel constructed across the slope.
-
Tree/Shrub Establishment (AC) (612)
(PDF; 23 KB)
- To establish woody plants by planting or seeding.
-
Waste Utilization (AC) (633)
(PDF; 62 KB)
- Using agricultural
waste or other waste on land in an environmentally acceptable
manner while maintaining or improving soil and plant resources.
-
Windbreak/Shelterbelt Establishment (FT) (380)
(PDF; 32 KB)
- Linear plantings of single or multiple rows of trees or shrubs
established for environmental purposes.
Table 1: Row-Types
Field Windbreak
Attributes |
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Description: |
One or more windbreaks or shelterbelts of closely spaced trees
and/or shrubs planted perpendicular to the prevailing troublesome
winds. "Wind shadows" created to the leeward side of
these barriers achieve desired purposes. A single windbreak may
consist of one to many rows to insure adequate density of branches,
stems and leaves. |
Some Primary FOTG Practices for this System: |
- Conservation Crop Rotation (328)
- Residue Management (329, 344)
- Cross Wind Ridges (589A)
- Cross Wind Stripcropping (589B)
- Cross Wind Trap Strips (589C)
- Herbaceous Wind Barrier (422A)
- Windbreak/Shelterbelt Establishment (380)
- Mulching (484)
- Irrigation System (441), Irrigation Water Management (449)
- Nutrient Management (590)
- Pest Management (595)
|
Primary Purposes: |
- Reduce wind velocity in the wind shadow area to: 1) control
wind erosion, 2) deposit snow uniformily, 3) increase crop quality
and production, and 4) improve water use efficiency.
|
Key Design Elements: |
- 35-60% density barriers (during the erosion period) with
the windbreaks at intervals across a field from 5H to 20H (agricultural
fields between windbreaks are generally greater than 200 feet wide).
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Low to moderate root and crown spread to minimize competition with adjacent crops.
- Resistance to pests and herbicides.
- Resistance to stem and branch breakage from high winds, ice, snow.
|
Livestock Windbreak
Attributes |
|
Description: |
A windbreak or shelterbelt of closely spaced trees and/or shrubs
planted perpendicular to the prevailing troublesome winds and
adjacent to livestock areas. Areas are generally settings where
livestock naturally concentrate or are confined such as a feedlot.
The "wind shadow" created to the leeward side of this
barrier achieves desired purposes. The windbreak may consist
of one to many rows to insure adequate density of branches, stems
and leaves. |
Some Primary FOTG Practices for this System: |
- Windbreak/Shelterbelt Establishment (380)
- Mulching (484)
- Use Exclusion (472)
- Fencing (382)
- Irrigation System (441), Irrigation Water Management (449)
|
Primary Purposes: |
- Reduce wind velocity to: 1) control energy loss and feed
intake by livestock, and 2) reduce snow drifting in the livestock
concentration area.
|
Key Design Elements: |
- 60-80% density barrier (year-round) with primary livestock areas within 5H of the barrier.
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Tolerance of nitrogen and phosphorus concentrations from manure.
- Resistance to pests.
- Some resistance to stem/branch breakage from high winds, ice, snow.
|
Farmstead Windbreak
Figure 3: Farmstead Windbreak
Includes drawings of a typical farmstead windbreak and the differences between protection
from snow and wind versus wind only.
Attributes |
|
Description: |
A windbreak or shelterbelt of closely spaced trees and/or shrubs
planted perpendicular to the prevailing troublesome winds and
adjacent to the farmstead home, buildings and work areas. The
"wind shadow" created to the leeward side of this barrier
achieves desired purposes. The windbreak may consist of one to
many rows to insure adequate density of branches, stems and leaves. |
Some Primary FOTG Practices for this System: |
- Windbreak/Shelterbelt Establishment (380)
- Mulching (484)
- Irrigation System (441), Irrigation Water Management (449)
- Diversion (362)
- Use Exclusion (472)
- Fencing (382)
|
Primary Purposes: |
- Reduce wind velocity to: 1) reduce energy loss, 2) trap snow
away from buildings, roads, etc. and 3) protect and improve human
habitat.
|
Key Design Elements: |
- 60-80% density barrier (year-round) with primary buildings/area
within 2-5H of the barrier but at least 100' from the windward
row in snow country. Animal waste runoff needs to be diverted
away from the windbreak.
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Aesthetically pleasing to increase farmstead value.
- When utility lines are present, low to moderate root and crown spread to reduce conflicts.
- Resistance to pests and herbicides.
- Resistance to stem and branch breakage from high winds, ice, snow.
|
Living Snowfence
Attributes |
|
Description: |
A planting of closely spaced trees and/or shrubs planted perpendicular
to the prevailing troublesome winds and adjacent to roads, buildings
and work areas. The "wind shadow" created to the leeward
side of this barrier achieves desired purposes by depositing
snow in deep drifts. A living snowfence may consist of one to
many rows to insure adequate density of branches, stems and leaves. |
Some Primary FOTG Practices for this System: |
- Windbreak/Shelterbelt Establishment (380)
- Mulching (484)
- Use Exclusion (472)
- Fencing (382)
|
Primary Purposes: |
- Concentrate snow deposition away from roads, buildings and other areas to improve farm access or habitat.
|
Key Design Elements: |
- 50-100% density barrier (snow season) with windward row at 100-200 feet from
road/area to be protected.
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Evergreens or densely branched trees and shrubs are preferred.
- Low to moderate root and crown spread to reduce conflicts with adjacent crops and utility lines.
- Resistance to pests and herbicides.
- Resistance to stem and branch breakage from high winds, ice, snow.
|
Alley Cropping
Attributes |
|
Description: |
Plantings consisting of trees or shrubs in rows or corridors
with alleys of agronomic crops or forage between. Plantings are
placed at intervals across a field or unit that, depending on
purpose, are perpendicular to the prevailing troublesome winds,
on the contour, or at multiples of the widest field equipment
width. The products derived from the trees or shrubs or the protected
or climatically influenced zones of these plantings achieve desired
purposes. Trees or shrubs planted along the edges of "alleys"
may consist of one to many rows to insure adequate density of
branches, stems and leaves. |
Some Primary FOTG Practices for this System: |
- Alley Cropping (new)
- Filter Strip (393), Conservation Crop Rotation (328)
- Stripcropping, Contour (585), Contour Farming (330)
- Residue Management (329, 344)
- Diversion (362), Terrace (600), Grassed Waterway (412)
- Use Exclusion (472), Fencing (382), Prescribed Grazing (528A)
- Pasture and Hay Planting (512)
- Mulching (484)
- Irrigation System (441), Irrigation Water Management (449)
- Nutrient Management (590), Pest Management (595)
|
Primary Purposes: |
- 1) To produce wood or tree products in addition to agronomic
crops or forage, 2) To improve crop or forage quality and quantity
by enhancing microclimatic conditions, 3) To improve utilization
and recycling of soil nutrients for crop or forage use, 4) To
reduce excess subsurface water or control water table depths,
5) To provide favorable habitat for species beneficial to crops
or forage.
|
Key Design Elements: |
- 30-100% density barriers with rows at intervals across field
to achieve intended purpose and tailored to equipment widths.
Intervals are wide enough to allow sufficient light to agronomic
crops in the alleys.
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Produce wood, fruit or fodder suited to the purpose of planting.
- Resistance to pests and herbicides.
- Tolerant of sediment deposition and pollutant-laden runoff
- Resistance to stem and branch breakage from high winds, ice, snow.
|
Contour Buffer Strips (woody species)
Attributes |
|
Description: |
Plantings consisting of tree/shrub rows on the contour or cross-slope,
and at multiples of the widest field equipment width. Tree or
shrub strips typically consist of two or more rows to insure
adequate root density and litter production, and are usually
planted in conjunction with strips of herbaceous vegetation.
|
Some Primary FOTG Practices for this System: |
- Contour Buffer Strips (new)
- Filter Strip (393), Conservation Crop Rotation (328)
- Stripcropping, Contour (585), Contour Farming (330)
- Residue Management (329, 344)
- Diversion (362), Terrace (600), Grassed Waterway (412)
- Use Exclusion (472)
- Mulching (484)
- Irrigation System (441), Irrigation Water Management (449)
- Nutrient Management (590), Pest Management (595)
|
Primary Purposes: |
- Reduce sheet and rill water erosion, increase sediment deposition
and convey excess water at a controlled grade.
|
Key Design Elements: |
- Barriers of closely spaced trees/shrubs planted at intervals
across the slope or on the contour and configured parallel with
one another as practicable. Intervals are wide enough to allow
sufficient light to agronomic crops between the strips. The spacing
between barriers should be in multiples of the widest field equipment
width and must not exceed the computations of spacings for constructed
terraces (see Terrace, 600, in the FOTG or NHCP). Typically,
suitable herbaceous vegetation is planted as part of the strip
to the uphill side of the woody vegetation.
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Resistance to pests and herbicides.
- Tolerant of sediment deposition and pollutant-laden runoff
- Fast-growing and dispersed root system.
|
Riparian Forest Buffer
Attributes |
|
Description: |
A corridor of trees and/or shrubs planted adjacent to a river,
stream, wetland or water body. The planting is of sufficient
width and up-gradient and near the water body to insure adequate
functioning for the desired purpose. |
Some Primary FOTG Practices for this System: |
- Riparian Forest Buffer (391)
- Streambank and Shoreline Protection (580)
- Use Exclusion (472)
- Fencing (382)
- Prescribed Grazing (528A)
- Pasture and Hay Planting (512)
|
Primary Purposes: |
- Protect near-stream soils from over-bank flows, trap harmful
chemicals or sediment transported by surface and subsurface flows
from adjacent land uses, or provide shade, detritus and large
woody debris for the in-stream ecosystem.
|
Key Design Elements: |
- Corridors are planted adjacent to and more-or-less parallel
with the stream bank. They must be sufficiently wide to achieve
primary purposes (usually 15 to 100 feet).
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Tolerant of extended periods of flooding (depending on the
width of the planting and distance from the streambanks).
- Moderate to aggressive root and crown spread to occupy the
site quickly and provide adequate litter fall.
- Resistance to pests and herbicides.
|
Filter Strip
Attributes |
|
Description: |
A strip or area of vegetation for removing sediment, organic
matter, and other pollutants from runoff and waste water. |
Some Primary FOTG Practices for this System: |
- Filter Strip (393)
- Conservation Crop Rotation (330)
- Stripcropping, Contour (585)
- Contour Farming (330)
- Residue Management (329, 344)
- Diversion (362), Terrace (600), Grassed Waterway (412)
- Use Exclusion (472)
- Fencing (382)
- Prescribed Grazing (528A)
- Pasture and Hay Planting (512)
|
Primary Purposes: |
- To remove sediment and other pollutants from runoff by filtration,
deposition, infiltration, or plant uptake.
|
Key Design Elements: |
- Strips are planted cross-slope or on the contour downhill
from the source of sediment or pollutants. They must be sufficiently
wide to achieve primary purposes.
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Tolerant of sediment deposition and pollutant-laden runoff.
- Moderate to aggressive development to occupy the site quickly.
- Resistance to pests and herbicides.
|
Multistory Cropping
Attributes |
|
Description: |
Plantings consisting of an overstory of trees or shrubs with
an understory of specialty or agronomic crops or forage. Tree-to-tree
distance is wide enough to let sufficient light through to understory
crops or forage. "Forest Farming" is a form of multistory
cropping. Tree canopies of native forests would be managed to
allow the production of such crops or forage. |
Some Primary FOTG Practices for this System: |
- Multistory Cropping (new)
- Tree/Shrub Establishment (612)
- Conservation Crop Rotation (328)
- Residue Management (329, 344)
- Use Exclusion (472) or Prescribed Grazing (528A)
- Pasture and Hay Planting (512)
- Nutrient Management (590)
- Pest Management (595)
- Irrigation System (441), Irrigation Water Management (449)
|
Primary Purposes: |
- 1) To produce wood or tree products in addition to agronomic
crops or forage, 2) To improve crop or forage quality and quantity
by enhancing microclimatic conditions, 3) To improve utilization
and recycling of soil nutrients for crop or forage use, 4) To
reduce excess subsurface water or control water table depths,
5) To provide favorable habitat for species beneficial to crops
or forage.
|
Key Design Elements: |
- Trees are planted or native forests managed at a sufficiently
wide spacing to allow adequate light to the understory crops
or forage and permit passage of the widest field equipment width.
Generally, mature tree canopy ranges from 5 to 40 percent crown
cover.
|
Tree/Shrub Species Requirements: |
- High value species adapted to the soil/climate of the planting site.
- Low to moderate root and crown spread to minimize competition with understory crops.
- Tolerance of agricultural fertilizers and traffic on surficial root.
- Resistance to pests and herbicides.
- High resistance to stem and branch breakage from high winds, ice and snow as applicable to the site.
|
Table 2: Block-Types
Wood Fiber Plantation
Attributes |
|
Description: |
Trees are planted in a block as a separate field within an agricultural
or livestock-production operating unit. Tree-to-tree distance
is adjusted to produce optimum amounts of wood fiber during rotations
generally less than 10 years. |
Some Primary FOTG Practices for this System: |
- Tree/Shrub Establishment (612)
- Use Exclusion (472)
- Nutrient Management (590)
- Forest Stand Improvement (666)
- Irrigation System (441), Irrigation Water Management (449)
|
Primary Purposes: |
- To produce tree products or wood fiber in close proximity
to agricultural or pasture areas to diversify the farm and ranch
products.
|
Key Design Elements: |
- Trees are planted at a spacing to optimize wood fiber production.
Generally, mature tree canopy cover ranges from 70 to 100 percent
crown cover.
|
Tree/Shrub Species Requirements: |
- High value species adapted to the soil and climate of the planting site.
- Tolerance of agricultural fertilizers and manure from adjacent fields.
- Resistance to pests and herbicides.
- Some resistance to stem and branch breakage from high winds, ice and snow as applicable to the site.
|
Water-Waste Management Planting
Attributes |
|
Description: |
A block planting of closely spaced trees and/or shrubs placed
downslope from agricultural water or waste sources. (For plantings
immediately adjacent to streams or water courses see Riparian Forest Buffer.)
The dimension of the planting on its downhill axis and distance
between individual plants insures the trapping of sediment or
harmful chemicals from uphill land uses. |
Some Primary FOTG Practices for this System: |
- Tree/Shrub Establishment (612)
- Use Exclusion (472)
- Prescribed Grazing (528A)
- Pasture and Hay Planting (512)
- Fencing (382)
- Waste Utilization
- Irrigation System (441), Irrigation Water Management (449)
|
Primary Purposes: |
- To use excess water by plant uptake, and/or intercept and
utilize or sequester waste and other pollutants transported from
uphill sources to and through a down-gradient block planting.
|
Key Design Elements: |
- Blocks are planted downhill from the source of water and/or
waste. They must be sufficiently large (generally greater than
100 feet on its downhill axis) to achieve primary purposes and
configured to fit the use of equipment and materials on adjacent
fields. Application of water and/or waste shall not exceed the
capability of the block planting to utilize such water/waste on
a sustained basis. (For plantings less than 100 feet wide, see
Filter Strips in the Alley
Cropping System.)
|
Tree/Shrub Species Requirements: |
- Adapted to the soil and climate of the planting site.
- Tolerant of excess water, sediment deposition and waste-laden runoff.
- Aggressive root and crown spread to occupy the site quickly.
- Resistance to pests, herbicides and site pollutants.
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