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Subject: Fodder trees
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Drought and consequent starvation is devastating Middle America at present.
The cost of converting fragile tropical forests to cattle ranches and row
crops is inevitably very high.  Though the production may be reduced,
because of their deeper root system and reduction of runoff, trees produce
crops in years when row crops may not even recover the planted seed.

Africans in arid areas have for thousands of years known this and planted
fodder trees for their livestock.  South American natives do not have that
tradition because the native forest cover provided sufficient food.  It will
be necessary for them to rebuild their forests, though difficult to do
because the rapacious timber industry and big cattle ranches have controlled
the governments.

The Overstory has some suggestions on scarifying seeds of fodder
trees---seeds produce trees with deep tap roots, cuttings produce trees with
shallow roots which have less resistance to drought and storm.

Welcome to The Overstory! This free e-mail journal serves subscribers in
151 countries. To subscribe (or unsubscribe), please see message at the end
of this e-mail.

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::::::::::::::
Overstory #91 - Fodder Tree Establishment

by James M. Roshetko and Ross C. Gutteridge

Contents:

: SITE PREPARATION
: SEED PREPARATION
: RHIZOBIUM INOCULATION
: VAM INOCULATION
: SEED SOWING
: VEGETATIVE PROPAGATION
: FIELD MANAGEMENT
: REFERENCES
: ORIGINAL SOURCE
: ABOUT THE AUTHORS
: WEB LINKS
: RELATED EDITIONS OF THE OVERSTORY
: PUBLISHER NOTES


Livestock play an important role in small-scale farming systems throughout
the world. Most often livestock graze fallow fields, pastures and woodlands
deriving most of their sustenance from crop residue, grasses and other
herbaceous plants. A smaller but important component of livestock diets
comes from tree fodder. Farmers harvest tree fodder from natural forests,
savanna and woodlots. Additionally, they often deliberately propagate trees
on their farms to expand fodder resources. Many of the most important
fodder trees are nitrogen fixing species. This article covers the
propagation, establishment, and maintenance of this important group of
nitrogen fixing trees used for fodder.

::::::::::::::
FODDER TREE ESTABLISHMENT

SITE PREPARATION
To minimize weed growth and competition, site preparation should occur
immediately before fodder tree establishment. Removal of vegetation can be
achieved by manual, mechanical, chemical or a combination of means. To
assure adequate establishment of nitrogen fixing fodder trees, it is
necessary to practice thorough site preparation. This is particularly
important in grass ecosystems, where fodder trees are often planted. The
objective of site preparation is a seed bed with limited weed competition,
where tree seedlings can thrive. At a minimum, remove all vegetation within
50 cm of the position where seedlings or seed will be planted. Both above
ground and below ground plant biomass (i.e. stems and roots) must be
removed. If rows of fodder trees are being established, meter-wide seed
beds the length of the rows must be prepared. For individual fodder trees,
seed beds one meter-diameter are sufficient.

A few precautions are warranted. The use of burning as a site preparation
method is not recommended, unless experienced personnel are present. The
removal of 100% of the vegetation from a site is not advisable. Complete
removal of the vegetation is costly and leaves the site vulnerable to soil
erosion. Furthermore, some of the existing vegetation may provide useful
fodder, mulch, fuel or other products.


SEED PREPARATION

Nitrogen fixing fodder trees are usually established by directly sowing
seeds or by transplanting seedlings. The seed of many of fodder species
have hard, waxy or thick seedcoats that inhibit water absorption and delay
germination. Under natural conditions, seedcoats are degraded by exposure
to sun, rain, wind and animals.

Uniform seedling size can be achieved through seed scarification - a
process designed to penetrate the protective seedcoat and allow seed to
absorb water and germinate at a uniform rate. The most common scarification
treatments are cool water, hot water, acid and nicking.

Cool water - Seeds are soaked in cool, room-temperature water until they
swell. The volume of water should be five times the volume of seeds.
Soaking time is 12-48 hours depending on species, provenance, age and
quality of seed. This treatment is appropriate for seeds with a thin or
soft seedcoat, recently harvested seed, seed of small-size, and large
quantifies of seed.

Hot water - Boiling water is poured over the seeds at a volume five times
the volume of seeds. The seeds must be stirred gently during the 2-5 minute
soak. Hot water can kill the seed - it is important not to soak the seed
for too long! Pour off the hot water, replace it with cool water and soak
for 12 hours. This treatment is appropriate for seeds with hard or thick
seedcoats, old seed, and large quantities of seed. It is best to treat a
small quantity of seed first to make sure your technique is correct before
attempting to treat large quantities of seed.

Acid - (CAUTION--Very dangerous--for laboratory professionals only) Cover
seeds with sulfuric acid for 10-60 minutes. Seed should be completely
submerged but just below the surface of the acid. Acid can kill the seed -
do not soak the seed for too long! Gauge the length of acid treatment by
the appearance of the seed. The waxy gloss of the seedcoat should be
replaced by a dull appearance. A pitted appearance indicates damage -
remove the seeds before this occurs. Remove seed from acid, rinse with
water for 10 minutes and soak in cool water for 12 hours. Do not pour water
into the acid or a violent reaction will occur! The acid can be used
several times. This treatment is appropriate for seeds with hard and thick
seedcoats. Acid treatment can be dangerous! In most circumstances it is not
recommended!

Nicking - Cut or scrape a small hole in the seedcoat. A knife, nail
clipper, file, sand paper or sanding block can be used for this operation.
To avoid damaging the seed embryo, cut or scrape the seedcoat opposite the
micropyle. Soak the nicked seed in water for 12 hours. This treatment is
appropriate for all types of seed, although nicking seed by hand is time
consuming and only feasible for small quantities. Large quantities of seed
may be nicked using a meat grinder, gristmill or thresher.

No treatment - Some seeds germinate quickly without treatment. Application
of the above methods may be impractical, make seed difficult to handle or
decrease viability. No treatment is needed for tiny seed (i.e., Desmodium
spp.); seeds with thin or incomplete seedcoats; and recalcitrant seed
(i.e., Erythrina edulis).

The length of the initial soak in cool water, hot water or acid will vary
according to species, provenance, age and quality of the seed. If large
numbers of seedlings will be produced, or nursery operations will last for
several years, it is recommended that several soaking times be tested in
order to determine the most suitable time length for local conditions. As
noted, with all methods the last process is to soak seed in cool water for
12 hours. This final process allows seed to absorb water, results in
visible swelling and further hastens germination. To improve this process,
and thus germination, this period may be increased up to 48 hours. Once
removed from the final soaking sow seed immediately! If sowing is delayed,
the seed will dehydrate resulting in decreased seed viability and weak
seedlings. The table below summarizes appropriate seed scarification
methods for common nitrogen fixing fodder trees.

Table . Seed scarification treatments for selected nitrogen species
(Revised from Macklin et al. 1989). (Key: A - Hot water;  B - Acid;  C -
Nicking;  D - Cold water;  E - No treatment)

Species    Treatments
Acacia acuminata C; D
Acacia aneura A; C
Acacia angustissima C; D
Acacia holosericea A for 1 min.; C
Acacia leucophloea A; B for 10-30 min.; C
Acacia me/anoxylon A; B for 15 min.; C
Acacia nilotica A; C; D
Acacia polyacantha D
Acacia salinga A; C
Acacia senegal C; D
Acacia seyal A; B; C
Acacia tortilis A; C; D
Adenanthera pavonina A for 1 min.; B
Albizia lebbeck A; C; D
Albizia adoratissima A for 1 min.; D
Albizia procera A; C
Albizia saman A; C
Cajanus cajan D; E
Calliandra calothyrsus A; C; D
Chamaecytisus palmensis A for 4 min.
Dalbergia spp. D
Desmodium spp. E
Enterolobium cyclocarpum C; D
Erythrina edulis E - (recalcitrant seed)
Erythrina poeppigiana D; C
Erythrina variegata A
Faidherbia albida A; B for 20 min.; C; D
Flemingia macrophylla A; B for 15 min.; D
Gliricidia sepium C; D; E
Leucaena spp. A; B for 5-15 min.; C
Ougeinia dalbergioldes D for 24 hours
Parasenanthes falcataria A; B for 10 min.; C
Pithecellobium dulce C; E
Pongamia pinnata E
Prosopis spp. A; C
Robinia pseudoacacia A; B for 20-60 min.; C
Sesbania grandiflora C; D
Sesbania sesban A; C; D




RHIZOBIUM INOCULATION

The seed of nitrogen fixing trees should be treated with Rhizobium inoculum
after scarification and prior to sowing. Rhizobium bacteria and NFTs form a
symbiotic relationship that enables the trees to "fix" atmospheric nitrogen
into a form useful for plant growth. This relationship allows NFTs to grow
on infertile or degraded soils where available nitrogen is in low supply.
The nitrogen fixation process occurs in nodules formed by the bacteria on
the tree roots. To determine the health of nodules cut them open. A red or
pink color indicates nodules are fixing nitrogen. Green, brown or black
nodules are not fixing.

There are many strains of Rhizobium bacteria. These strains and NFTs often
exhibit exclusive preferences for each other. Some bacteria will form
nodules with some NFTs but not others. Likewise, trees may form nodules
with many strains or just a few. A successful match will produce healthy
nodules. If an NFT is native or naturalized in an area, the soil will
likely contain appropriate Rhizobium strains. However, if the tree does not
occur locally, or the site is degraded, populations of the appropriate
Rhizobium strains may be too low to form healthy nodules.

To assure an effective Rhizobium-NFT match, it is best to use a Rhizobium
inoculant. Inoculants are produced in laboratories and contain 1000 times
the bacteria found in most soils. The bacteria in the inoculants are alive.
They are sensitive to heat, dehydration, direct sunlight and low
temperatures. It is best to use inoculants when received - viability
decreases greatly after 6 months. When storage is necessary, the inoculant
should be placed in an airtight bag (being sure to exclude all air) and
stored in a moist, cool and dark place. When ordering inoculants be sure to
specify the NFT species you plan to inoculate.

To apply inoculants, first cover seeds with a sticker solution. Place seeds
in a plastic bag or bucket and cover them with a solution made of gum
arabic, sugar or vegetable oil. Either dissolve 40 g of gum arabic in 100
ml of hot water and allow to cool, or dissolve 1 part sugar in 9 parts
water. Combine 2 ml of one of these mixtures, or 2 ml of vegetable oil,
with 100 g of seeds and shake or stir until the seeds are well coated. Then
add 5 mg of inoculant and shake or stir until the seeds are well covered
with inoculant. Allow the inoculated seeds to dry for 10 minutes to
eliminate any stickiness and sow immediately. Do not store inoculated seed
- the bacteria will die.

Seedlings can also be inoculated in the nursery after germination. Mix
inoculant in cool water and irrigate the seedlings with the suspension.
Keep the mixture well shaken and irrigate until the inoculant is washed
into the root zone. A 50 g bag of inoculant is sufficient to inoculate
10,000 seedlings. For more information on the NFTs-Rhizobium relationship
and inoculation methods consult Keyser (1990), Postgate (1987) and
Somasegaran and Hoben (1985).

It may not always be possible to obtain laboratory-produced inoculant. At
such times, soil containing the appropriate bacteria can be gathered from
under trees of the same species being grown in the nursery. Choose healthy
trees that are growing well and have abundant red or pink nodules. Some of
this soil can be mixed with nursery potting mix or added to planting pits.
Inoculation by this method assures that the bacteria will be appropriate
for the tree species and the local environment. However, this approach may
not be as effective as using a correct laboratory-produced inoculant.


VAM INOCULATION

Like Rhizobium, vesiculararbuscular mycorrhizal fungi (VAM) are soil
organisms that invade the roots of NFTs and other plants to form symbiotic
relationships. Plants provide VAM food in the form of carbohydrates. VAM
infection improves plant survival and growth by enhancing the root's
ability to absorb moisture, macro-nutrients and micro-nutrients from the
soil. Increased access to phosphorus is a specific advantage of VAM
symbiosis. This relationship helps plants to colonize infertile or degraded
sites. Unlike other mycorrhizae, VAM does not produce visible external
hyphae;  its branched hyphae are mainly contained within the infected root.
The spores of VAM are formed near infected roots in the organic layer of
the soil. They are large and are not disseminated by wind like the spores
of other mycorrhizae. To assure the VAM plant association, seedlings or
seed should be inoculated in the nursery. Inoculation is particularly
important when trees are to be planted on degraded sites where the organic
soil has been removed.

VAM inoculation is usually accomplished by incorporating the organic soil
from beneath a healthy host-plant into the nursery soil at a rate of 5-10%
per volume. This method is simple and appropriate for most farm-level or
community nurseries. However, it entails moving large amounts of soil and
may transfer pathogens from forest soils to the nursery. It is not possible
to sterilize forest soils because the process will also kill the VAM. For
larger nurseries, a second option is to construct a "VAM production bed."
First, collect infected soil as described above and completely fill a
nursery bed. Next, sow seed of the appropriate host plant at a close
spacing. Once well established, the roots of the infected plants, and VAM,
will permeate the soil in the nursery bed. Remove the soil and roots, and
then finely chop and mix them into the nursery soil as an inoculant at a
rate of 5-10% per volume. This method, while more expensive and management
intensive than collecting soil beneath a healthy host-plant, is appropriate
if many seedlings are to be produced over a number of years. Healthy
host-plants should be maintained in the VAM production bed to assure
continued supply of VAM inoculant.

Recent advances in technology have made laboratory production of VAM
inoculants practical. Several commercial inoculants are available which are
appropriate for NFTs. Readers interested in more information on VAM and
inoculation are encouraged to consult Casetellano and Molina (1989),
Ferguson and Woodhead (1982), and Malajczuk et al (undated).


SEED SOWING

As previously mentioned, seed can be sown in the nursery or directly in the
field. In either case, the seed bed or nursery soil should be well
cultivated and free of weeds. Seeds should be sown in the soil to a depth
of once or twice their width. In field plantings where rapid soil drying is
likely to occur, the depth of sowing can be increased to 10 times the width
of the seed. The seed should be covered with soil, sand or mulch. When
using mulch, be sure it does not contain weed seeds! For most species
germination will occur within 1-3 weeks. Young germinants are sensitive to
dehydration, weed competition and insects. Care must be taken to guard
against these dangers.

For nursery production, standard local nursery methods are recommended.
Further information on nursery practices and management is available in
standard texts on the subject. Depending on the species, seedlings are
ready for transplanting to the field after 6-16 weeks in the nursery.
Seedlings should be "hardened" in direct sunlight for at least one week
before transplanting, preferably at the beginning of the wet season.
Because of the large number of trees planted in most fodder production
systems, establishment is usually achieved by direct sowing. This method is
more cost-effective than nursery production, however, there is less control
over the planting site. Direct sowing operations should be conducted only
during the rainy season.


VEGETATIVE PROPAGATION

Some nitrogen fixing fodder species can be established from vegetative
cuttings. Propagation techniques differ greatly from species to species but
generalizations are possible. Gliricidia sepium and most Erythrina species
are commonly propagated by large cuttings 1-3 meters in length. Albizia
spp. and Dalbergia spp. and Ougenia dalbergioides are also reproduced by
small stem cuttings 15-20 cm in length and 1.0-1.5 cm in diameter.

Straight and healthy stems, branches, coppice growth or roots are
recommended for vegetative propagation. Branch cuttings may retain their
original morphology resulting in crooked trees. While crooked trees are not
aesthetically pleasing, their morphology has no negative effect on fodder
production or quality. Cuttings are usually harvested at the end of the dry
season or beginning of the rains. The use of sharp clean tools will produce
healthy undamaged cuttings. The cuttings of some species can be stored for
up to 15 days before planting. Storage should be in a cool, dry and shady
place with good aeration. Do not pile cuttings directly on the ground.
Large cuttings should be stored vertically.

Water accumulation on the tips of cuttings can cause stem rot. To avoid
this problem the apical (top) end of cuttings should be cut at a 45 degree
angle. Rooting is promoted by scarring the lower portion of the cutting
which will be buried. Scarring should be done with a sharp knife and should
penetrate the cambium. If available, treat scars with a rooting hormone.
Cuttings should be planted, not pushed into the ground causes damage to the
bark and result in weak roots. Large cuttings should have 30% of their
length buried in the soil. Small cuttings should have 50-75% of their
length buried.

It should be noted that cuttings generally produce shallow root systems
without a strong, deep taproot. Shallow root systems leave trees vulnerable
to drought and blow-down during windstorms. Also, while cuttings provide
quick establishment, time-and labor-costs per plant are greatly increased.
Therefore in most fodder production systems, propagation by seed is
preferred.


FIELD MANAGEMENT

After germination or transplanting, the top growth of most nitrogen fixing
fodder seedlings is slow. Initially, the seedling's growth energy is
allocated to root system development. While this growth pattern aids
long-term tree survival, it does not assist young seedlings become
established among pre-existing vegetation - even where adequate site
preparation has been completed. In most ecosystems, competition for
sunlight, soil moisture and soil nutrients is intense and young
slow-growing trees are often the losers. Competition is particularly
intense when trees are planted in grass ecosystems. Grasses, and other
herbaceous plants, have intensive root systems with many fine roots which
densely permeate the upper soil layers. By contrast, trees have extensive
root systems with thick roots which sparsely penetrate large volumes of
soil. Grasses and trees are ecologically antagonistic, once present,
grasses often prevent the establishment of trees.

When trees are small, grass and other weed competition must be controlled.
While management regimes differ by site and species, a good recommendation
is to remove all vegetation within 50 cm of the trees every 2-4 weeks. The
objective is to deny weeds the opportunity to impede tree growth. As trees
gain size, the frequency of weed control operations can be reduced.
However, weed control must be maintained until the trees achieve a dominant
position and begin to suppress competing vegetation. This usually occurs
within 6-12 months of tree establishment. It is not necessary or desirable
to remove 100% of the weed competition. Some vegetation - particularly
grasses - are valuable fodder and improve the overall productivity of the
fodder production system.

Fertilizer application can improve fodder tree growth and survival.
However, little information is currently available concerning appropriate
fertilization regimes for most fodder trees. A detailed study undertaken at
the University of Queensland in Australia indicated that Leucaena
leucocephala has a high requirement for phosphorus and calcium. On
infertile soils, growth responses will occur at rates up to 225 kg P/ha and
230 kg Ca/ha. However, if the L. leucocephala plants have formed an
association with VAM much lower rates of phosphorus fertilizer give the
same response.

When fertilizers are applied it is essential to practice thorough weed
control. The intensive root systems of herbaceous weeds respond quickly to
fertilizer application. Trees respond more slowly. Left unchecked, weeds
will suppress trees. Fertilization without adequate weed control results in
decreased fodder tree survival and growth. In rural areas, fertilizers can
be expensive or unavailable. For these reasons, fodder trees on small-scale
farms are generally not fertilized.

The longevity of fodder trees is increased when the first harvest is
delayed until trees are 9-21 months old. Actual age at first harvest
depends on environmental conditions and tree growth. Under arid or poor
soil conditions, growth will be slow and the first harvest should be later.
When growth is fast, the first harvest can be sooner. The goal is to allow
trees to establish deep roots. The resultant healthy plants will have ample
carbohydrate reserves to resprout quickly and vigorously after harvesting.
Fodder production per harvest and long-term fodder production both increase
when the first harvest is delayed. The first harvest, whether by cutting or
grazing, may terminate the downward growth of the roots. This is an
important consideration, particularly in arid and semi-arid environments.

Fodder trees are a valuable crop that can sustain or increase livestock
production. They should be managed intensively. Most often fodder trees are
established in integrated systems with grasses or other fodder crops. While
trees and herbaceous plants are ecologically antagonistic, their fodder
products are complementary, together forming well-balanced livestock diets.
Fodder trees should be managed to improve the livestock production system,
not necessarily to maximize tree growth or tree fodder production.


::::::::::::::
REFERENCES

Castellano, M.A. and R. Molina. 1989. Mycorrhizae. In: T.D. Landis, R.W.
Tinus, S.E.

McDonald, and J.P. Barnett, eds. The container tree nursery manual, Volume
5. Washington DC, USA: USDA Forest Service, pp 101-167.

Ferguson, J.J. and S.H. Woodland. 1982. Production of endomycorrhizal
inoculum: A. Increase and maintenance of vesicular-arbuscular mycorrhizal
fungi. In: N.C. Schenck, ed. Methods and principles of mycorrhizal
research. St. Paul, Minnesota, USA: American Phytopathological Society, pp
47-54.

Keyser, H. 1990. inoculating tree legume seed and seedlings with rhizobia.
Paia, Hawaii, USA: Nitrogen Fixation in Tropical Agricultural Legumes
(NifTAL) Center, 2 pp.

Liegel, L.H. and C.R. Venator. 1987. A technical guide for forest nursery
management in the Caribbean and Latin America. General Technical Report
SO-67. New Orleans, Louisiana, USA: USDA Forest Service, Southern Forest
Experiment Station, 156 pp.

Macklin, B., N. Glover, J. Chamberlain, and M. Treacy. 1989. NFTA
Cooperative Planting Program establishment guide. Morrilton, Arkansas, USA:
Forest, Farm and Community Tree Network (FACT Net), Winrock International,
36 pp.

Malajczuk, N., N. Jones, and C. Neely. Undated. The importance of
mycorrhiza to forest trees. Land Resources Series - No. 2. Washington, DC,
USA: The World Bank, Asia Technical Department, 10 pp.

Postgate, J.R. 1987. Nitrogen fixation, second edition. The Institute of
Biology's studies in biology. London, UK: Edward Arnold LTD, 73 pp.

Shelton, H.M. 1994. Establishment of forage tree legumes. In: R.C.
Gutteridge and H.M. Shelton, eds. Forage tree legumes in tropical
agriculture. Wallingford, UK: CAB Interna-tional, 139 pp.

Somasegaran, P. and H.J. Hoben. 1985. Methods Legume-Rhizobium Technology.
Paia, Hawaii. NifTAL Center, 367 pp.


::::::::::::::
ORIGINAL SOURCE

With the kind permission of the authors and publisher, this article is
excerpted from:

Roshetko, J.M. and R.C. Gutteridge (Editors). 1996. Nitrogen Fixing Trees
for Fodder Production: a field manual. Forest, Farm, and Community Tree
Network (FACT Net), c/o Winrock International. Morrilton, Arkansas, USA.

A hardcopy of this book is available for purchase from:

Winrock International
FACT Net
38 Winrock Drive
Morrilton, AR 72110-9370  USA
Tel: 501-727-5435; Fax: 501-727-5417
Email: forestry AT winrock.org
Web Site: http://www.winrock.org/forestry/factnet.htm


::::::::::::::
ABOUT THE AUTHORS

Jim Roshetko has worked with agroforestry systems and tree species for 15
years in Southeast Asia, South Asia, the Pacific and the Caribbean.  He is
currently based in Bogor, Indonesia as a Tree Domestication and Training
Specialist with Winrock International and the International Centre for
Research in Agroforestry (ICRAF).  His work focuses on enhancing
smallholder tree farming systems.  He can be contacted at: ICRAF/Winrock,
PO Box 161, Bogor 16001, Indonesia; Phone 62 251 625-415; Fax 62 251
625-416; email: <J.Roshetko AT cgiar.org>.

Ross Gutteridge is Senior Research Fellow at the School of Land and Food
Sciences, the University of Queensland, Australia. He has worked on
agroforestry projects throughout Southeast Asia and the Pacific. He is
currently involved in a Leucaena evaluation and development program in
Vietnam. His books include Forage Tree Legumes in Tropical Agriculture (CAB
International) and Leucaena (ACIAR). He can be reached at: School of Land
and Food Sciences, The
University of Queensland, Queensland 4072, Australia; E-mail:
<r.gutteridge AT mailbox.uq.edu.au>.

::::::::::::::
WEB LINKS

FACT Net's common nitrogen fixing trees for fodder production summarized by
mean annual rainfall and mean annual temperature:
<http://www.winrock.org/forestry/factpub/FODDER.HTM>

FACT Net's very popular fact sheets on multipurpose species can be viewed
at: <http://www.winrock.org/forestry/factpub/factsh.htm>

Forage Tree Legumes in Tropical Agriculture (1998) edited by Ross C.
Gutteridge and H. Max Shelton, is available on the internet at:
<http://www.fao.org/ag/AGP/AGPC/doc/Publicat/Gutt-shel/x5556e00.htm>

The US Department of Agriculture National Agroforestry Center's
publications include silvopasture <http://www.unl.edu/nac/afnotes/>

::::::::::::::
RELATED EDITIONS OF THE OVERSTORY

The Overstory #65--Biological Nitrogen Fixation
<http://www.agroforester.com/overstory/overstory65.html>
The Overstory #37--Trees/Livestock Examples
<http://www.agroforester.com/overstory/overstory37.html>
The Overstory #36--Silvopasture
<http://www.agroforester.com/overstory/overstory36.html>
The Overstory #35--Animals in Agroforestry
<http://www.agroforester.com/overstory/overstory35.html>
The Overstory #4--Nitrogen Fixing Trees
<http://www.agroforester.com/overstory/overstory4.html>

::::::::::::::
PUBLISHER NOTES

Publisher: Permanent Agriculture Resources, P.O. Box 428, Holualoa, HI
96725 USA; Tel: 808-324-4427; Fax: 808-324-4129; E-mail:
<par AT agroforestry.net>; Web site: <http://www.agroforestry.net>

Editors: Craig R. Elevitch and Kim M. Wilkinson

Past editions of The Overstory: <http://www.overstory.org>

This publication is Copyright 2001 Permanent Agriculture Resources.  All
rights reserved worldwide. For conditions of use please send an e-mail to
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