can benefit another.

rees require sunlight, carbon dioxide, water, and nutrients to
Terow. Waste from municipal sewage treatment plants,
livestock operations, irrigated farming operations, and industrial
processing contains nutrients that can be used by trees. Trees
can often be substituted for more costly engineered practices.

Of the nutrients commonly found in these wastes, large
amounts of nitrogen, phosphorus, potassium, magnesium,
calcium, and sulphur are needed by trees in large quantities.

The nutrients taken up are distributed throughout cells in the
tree, with the highest concentration ending up in the leaves. The
leaves conduct photosynthesis, the process by which sunlight is
used to convert carbon dioxide into sugars that accumulate
primarily in the wood. Year after year, as the tree grows,
nutrients are stored in the wood of branches, stems, and roots.
Rapidly growing trees provide a better sink for these wastes
than older trees.

In addition to the benefit of using the nutrients from wastes, the
trees can be harvested after six to 15 years, depending on
species and climate. Products derived from the wood can
provide a substantial cash return to the landowner or operator.

Water and oxygen
are released into
atmosphere _

For growth, trees
require:

v Sunlight

Vv Carbon dioxide

v Water » Photosynthesis
V Nutrients - consumes

atmospheric CO
and produces
sugars used for

Nutrients and plant growth

water in liquid
waste @

are degraded
within the

Nutrients
in biosolids @

Fine roots absorb
nutrients, acting
as a “biofilter.”

Deep roots uptake
nutrients not ab-
sorbed by surface
roots

Open to learn more

Waste from one species

Fast growing trees, such as hybrid poplars,
can take up large amounts of nutrients,
making them ideal for treating wastes.

Which trees?

Success in using trees to remove
wastes depends on the species and the
length of the growing season. Trees
that are well-suited for treating wastes
include several species with rapid
growth rates, which allow more
nutrients to be absorbed than trees that
grow more slowly. Extensive and deep
root systems are also desirable,
enabling nutrients to be effectively
filtered out and keeping them from
moving into ground water.

Fast growing tree species that can be

planted for nutrient uptake include:

¢ Hybrid poplar (grows in many
regions of the U.S.)

¢ Hybrid willow (Northeast U.S.)

¢ Sweetgum, sycamore, and yellow
poplar (Mid-Atlantic and Southeast
US.

S)
* Loblolly pine (Southeast U.S.)

Both hybrid poplar and hybrid willow
are especially attractive because of
their ease of regeneration.

When selecting trees for eventual
harvesting, check with local mills
on the potential market for wood

products.



_.. In Communities

Municipal and Industrial Waste

Management of municipal and industrial effluent and
biosolids is becoming increasingly challenged, as
stricter regulations to improve water quality are
imposed within our Nation’s rivers, lakes, and ground
water. The beneficial use of municipal and industrial
wastes in tree plantations is one of the innovative
approaches being developed. The trees use nutrients in
the effluent and biosolids that would otherwise
contribute to the problem of nutrient loading in the
streams. In addition, the plantations enhance
landscape aesthetics, and generate income from the
production of wood products.

Benefits and Opportunities

Economic—A direct economic benefit is obtained
from the sale of wood products. Wood products can be
in the form of chips, fuelwood, mulch, veneer, lumber,
paneling, molding, and specialty products. This helps
offset the cost of treatment, making it less expensive
than most structural treatment alternatives.

Aesthetic—The visual environment can be improved
by providing a buffer to adjacent land uses. Also, the
tree plantation can help reduce the drifting of odors to
neighbors and communities.

Environmental—Working trees protect water quality
and safeguard clean water supplies for communities,
fish, wildlife, recreation, and people. Tree plantations
provide wildlife habitat for a variety of birds and
animals. The tree canopy catches dust particles and air
pollutants, thereby improving air quality. Trees store
carbon dioxide in their wood as they grow, and can
contribute greatly to reducing atmospheric carbon
dioxide levels. Carbon credits, whose value will be
market based, may be sold to industries and utilities.
The amount of carbon dioxide stored in a tree
plantation will depend on the species, growth rate, age,
and management.



Will it work for you?

Planning
considerations

Where to get more

In considering whether or not to use trees to treat waste in your particular situation,
answer the following questions. Technical assistance is available to accurately
determine some of the information.
Q Do you have available land with adequate soils for tree growth?
Q What is the composition and amount of the waste material?
* Quantity (volume and/or flow rate)
* Quality (concentration of nutrients and heavy metals)
¢ Form (liquid or solid)
Qa Does the need for dealing with these materials coincide with the growing
season? If not, is there adequate storage for waste accumulated during the
winter months?

Q Are you willing to commit time and resources for the planning, design,
installation, and maintenance of the trees?
Q What is the desired end use for the trees? (timber, aesthetics, wood chips)

¢ Acreage (optimal size needed for increased profits)
* Cooperatives (harvesting and marketing advantages)
¢ Products mix

The harvesting of animal waste requires special consideration and should be part of a

comprehensive nutrient management plan (CNMP). For further assistance contact
your local Natural Resources Conservation Service (NRCS) field office.

Developing a successful program for using trees to treat waste is not a do-it-yourself

information project. Specialists are available in both the public and private sectors. For more
information at the national level, contact the USDA, National Agroforestry Center
(NAC), East Campus — UNL, Lincoln, NE 68583-0822. Telephone (402) 437-5178, or
visit NAC’s web site at www.unl.edu/nac.
For local assistance, contact your nearest USDA, NRCS office, County Extension
Office, Soil and Water Conservation District, State Forestry agency, state water
quality agency, state land grant university, and/or reputable consultants working in
this field.
National This brochure was developed by the USDA National Agroforestry Center (NAC) in
cooperation with Washington State University, The Upper Columbia Resource Conservation
Agroforestry and Development Council (RC&D), and Greenwood Resources, Inc.
Center NAC’s Mission: The USDA National Agroforestry Center is a partnership of the USDA Forest
Service, Research & Development (R&D) (Rocky Mountain Research Station), and State &
Private Forestry (S&PF) and the USDA, Natural Resources Conservation Service. The Center's
purpose is to accelerate the development and application of agroforestry technologies to attain
more economically, environmentally, and socially sustainable land-use systems. To accomplish
its mission, the Center interacts with'a national network of cooperators to conduct research,

develop technologies and tools, establish demonstrations, and provide useful information to
natural resource professionals.

Address: USDA National Agroforestry Center, East Campus - UNL, Lincoln, Nebraska 68583-
0822. For a supply of brochures, contact Nancy Hammond, e-mail nhammond@fs.fed.us or

A partnership of the fax (402) 437-5712. For more information on the Center, contact Rich Straight, 402-437-5178
Forest Service and ext. 24 or Bruce Wight, ext. 36.

Natural Resources The United States Department of Agriculture (USDA) prohibits discrimination in all its
Conservation Service programs and activities on the basis of race, color, national origin, gender, religion, age

NPS 00-0254

disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited
bases apply to all programs.) Persons with disabilities who require alternative means for
communication of program information (Braille, large print, audiotape, etc.) should contact
USDA's TARGET Center at (202) 720-2600 (voice and TDD).

To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room
326W, Whitten Building, 14th & Independence Ave., SW, Washington, D.C., 20250-9410 or
call (202) 720-5964 (voice or TDD). USDA is an equal opportunity provider and employer.


cess nutrients and other
Bsn from agricul-
tural, municipal, and industrial
operations impact surface and
ground water quality. Plant
science and engineering have
combined forces forming a
natural partnership between
treating waste and growing trees.
The technology of putting fast
growing trees to work recycling
nutrients from solid and liquid
waste is available and increas-
ingly being adopted. This waste
treatment approach has emerged
as an alternative to other more
expensive treatment technolo-
gies, such as constructed
treatment plants.

What to do? Turn waste into a
product by applying it to trees.
This waste is actually a nutrient
and water source for trees. Trees
absorb excess nutrients and
breakdown harmful chemicals,
providing a natural cleaning
process for soil and water
resources. A major advantage is
that trees can be used for a
variety of products generating
extra income that can potentially
diversify the rural economy. Tree
plantings also provide visual,
noise, and odor buffers, while
directly aiding in reducin,
atmospheric carbon dioxide by
storing carbon in the wood and
soil.

Working Trees
for Treating Waste

A natural alternative for using nutrients from livestock
and farm operations, municipalities, and industries.

The increase in atmospheric
carbon dioxide levels has be-
come a worldwide concern.
Trees use carbon dioxide

for growth and store lar
amounts of carbon in wood
tissue, both above and below
ound.

These hybrid poplars are nourished by
wastewater from an industrial plant.

Is it right for your operation?
This publication addresses the
concept of using trees to treat
waste and also some key
management questions to ask
yourself before trees are put to
work as your natural solution
to water pollution.


On Agricultural Land...

Irrigation Tailwater

Excess irrigation water applied to crops contains high levels
of nutrients (nitrogen, phosphorous, potassium), pesticides,
and other compounds. Unless treated, this contaminated
water will eventually reach surface and ground water. Trees
can be planted to intercept this drainage water, or the water
can be diverted, stored in a pond, and then applied to tree
plantations. The trees can recycle this water, use many
excess nutrients, and break down hazardous pesticides and
other compounds. Tree species selection, irrigation water
management, and soil and water quality monitoring are
important planning elements to assure tree plantations
accomplish their multiple purposes.

Animal Waste

Livestock operations, such as dairies, hog confinements,
cattle feedlots, and poultry barns, generate both solid and
liquid waste. Applying this waste to tree plantations is
recognized as a treatment alternative throughout the United
States. These tree plantations can also serve as a visual
buffer to livestock operations and can reduce the drift of
odors. Tree species need to be tolerant of high salt and
sodium levels. Monitoring soil and ground water nutrient
and pathogen levels will be important to protect water
quality, where high levels of nutrients are applied to limited
acreage (maximum loading). Treat the greatest number of
acres possible to achieve a return on your investment from
the harvest of wood products. It is important to use qualified
technical assistance, conservation planning, and obtain
appropriate permits.

Development and Site Management

Productive tree plantations used to recycle waste require close attention
to tree establishment, stand management, and irrigation system design
and monitoring. Since these working tree plantations are dual purpose
plantings, itis important that adequate tree growth occurs to both
sufficiently use the waste and produce a wood product. Below are some
key planning considerations:

Soils/site — The best sites have deep loamy soil for good root
development, as highly porous soil can contaminate ground water.
Suitability of soils/site depends on tree species selected. Other
considerations include slope, proximity to surface water, and proximity
to people.

Tree species selection — Trees should be suited to the soil and have
growth characteristics conducive to high nutrient uptake. Wood product
qualities can be important selection criteria.

Tree spacing — Spacing affects future tree size and wood product
potential as well as how rapidly the canopy will close.

Stand establishment — Proper site preparation, planting, and
maintenance are essential to maximize tree growth. Three to five years
of weed control are needed to establish trees, depending on species and
initial spacing.

Management — The tree plantation should be protected from
animals (livestock, deer, mice/voles) during establishment. Eventually,
the trees may need to be thinned and pruned if high quality sawlogs are
an intended product.

Irrigation system design/monitoring — The quantity and quality of waste
being applied is important. The delivery system must efficiently apply the
waste to maximize waste/nutrient uptake. Monitoring nutrient loading rates
and water requirements of the trees is important for sustainable tree growth
while protecting ground water quality.

Nutrient uptake of tree Nutrient
stand (200 to 360 pounds ;

of nitrogen per acre per water

year) uptake by

tree age

Water use of tree
stand (25 to 45 inches
of water per acre per
year)

QUANTITY

TIME (age of tree stand)



Putting trees to work on
waste and waste water. . .