Greater Plant and Soil Health for Less Work

Why Mulch?

Agriculture with mulch in the tropics promotes plant health and vigor. Mulching improves nutrient and water retention in the soil, encourages favorable soil microbial activity and worms, and suppresses weed growth. When properly executed, mulching can significantly improve the well-being of plants and reduce maintenance as compared to bare soil culture. Mulched plants have better vigor and, consequently have improved resistance to pests and diseases.

"Mulch" is a layer of decaying organic matter on the ground. Mulch occurs naturally in all forests; it is a nutrient rich, moisture absorbent bed of decaying forest leaves, twigs and branches, teeming with fungal, microbial and insect life. Natural mulch serves as a "nutrient bank," storing the nutrients contained in organic matter and slowly making these nutrients available to plants. All forms of plant life from the ground layer to shrubs and trees thrive, grow, shed organic matter, die and decay, in a complicated cycle of nutrients.

Mulch forms a necessary link in nutrient cycling vital for our soils. When mulch is absent for whatever reason, the living soil is robbed of its natural nutrient stores, becomes leached and often desiccates. Natural environments without a litter layer are usually deserts. Non-desert plants grown in bare soil require constant fertilization, nutrient amendment and water, not to mention the work required to keep the soil bare.

Sheet mulching as described here is a suggested method for controlling weeds and improving soil and plant health with mulch. The process mimics the litter layer of a forest floor.

Basic Techniques of Sheet Mulching

Once you get the hang of it, sheet mulching can be used anywhere plants are grown in the ground. Sheet mulching may be used either in establishing a new garden or tree planting, or to enrich existing plantings. In both cases, mulch is applied to bare soil or on top of weeds. New plantings are planted through the mulch, and a small area is left open to accommodate established plants and trees.

The benefits of mulching justify putting the energy into doing the job right, using ample materials. Collect all of the materials (as outlined below), and complete the mulching process in a day. A reduction in maintenance and increase in plant vigor will reward the initial effort.

Sheet mulch is put down in layers to mimic natural forest mulch: well decayed compost, weed barrier, partly decayed compost and raw organic matter.

How to sheet mulch

Step 1: The Concentrated Compost Layer

To prepare the site, knock down tall weeds and woody plants with a brush cutter, scythe, or simply by trampling the area. Then proceed to lay down the sheet mulch.

Whether you are mulching bare soil or weeds, the first step is to "jump start" microbial activity by adding enriched compost, poultry or stock manure, worm castings or the like at the rate of about 50 lbs/100 square feet. This high nitrogen matter stimulates soil life and gets things going. If the soil is acid, which it likely is if the area has been disturbed recently and treated with conventional fertilizers, add a layer of lime or crushed coral. A soil analysis will indicate the need for adjustment of pH or mineral amendments. This is the appropriate time to add the recommended doses of amendments such as rock phosphate and K mag.

Soak the area well with water when the amendments are dispersed.

Step 2: The Weed Barrier

Most cultivated areas today harbor untold numbers of weed seeds. There are also weed seeds carried around by wind, animals and people. Soil borne seeds are lying dormant and waiting for the right conditions to sprout. Simply pulling or killing growing weeds will not erase the weed problem: more seeds will sprout almost as soon as the soil is exposed to moisture and light. Therefore the next step in mulching is to put down an organic weed barrier. This barrier prevents the germination and eventual emergence of weeds through your mulch.

Underneath this weed barrier grasses and weeds die and quickly become food for earthworms. From now on, the worms turn and aerate the soil, as they do naturally when in the right environment.

Of the four sheet mulch layers, the weed barrier has no natural counterpart on the forest floor. In the forest, weeds do not sprout because there is "no room for them," which simply means a lack of space above and below the ground, and a lack of light. By planting an area properly, there will eventually be no room for weeds. The weed barrier is needed only for establishment of the mulch, and disappears with time. If your area is planted appropriately, weeds will not emerge after the decomposition of the weed barrier.

Materials for the weed barrier that work well are: 4-6 sheets of newspaper, cardboard, burlap bags, old rugs of natural fiber, worn-out jeans, gypsum board, or whatever you can find around. Banana, ape and ti leaves also work if laid down in several layers. Overlap the pieces of the material so as to completely cover the ground without any breaks, except where there are plants you want to save. Around these leave a generous opening for air circulation around the root crown. Care in laying down the weed barrier will save you the headache of emerging weeds later on.

Step 3: The Compost Layer

This layer is on top of the weed barrier - it must be weed seed free. Well conditioned compost, grass clippings, seaweed and leaves are ideal materials to spread over the weed barrier. Any weed-free material mixture at the right moisture level for a good compost will do. This should form a fairly dense layer about 3 inches thick.

Step 4: The Top Layer

The top dressing mimics the newly fallen organic matter of the forest. It also must be weed-free. Good materials for this include leaves, twigs and small branches, fern or palm fronds, straw, coffee chaff, macadamia nut shells, wood chips, sawdust, bark, etc.. The top layer will slowly decompose into lower layers, and therefore must be replaced periodically; it represents reserves of compost. This layer should be about 3-5 inches deep. Many materials suitable for the top layer often have a pleasant cosmetic appearance. What luck! For this reason, there should be no hesitation in using sheet mulch in all cultivation from landscaping to gardening to permanent orchard crops. In fact, as you use mulch, bare soil will begin to seem ugly and undesirable.

When the soil is amended and sheet mulch applied properly, there will never be a need to turn the soil. Earthworms do the tilling. The only task left will be to keep the soil covered by replenishing the mulch.

Warning: Feral pigs love good, moist soil, and will grub in sheet mulch if they have access to it. Do not use sheet mulch if pigs have access to the area; they will be attracted to it and will destroy both your work and your plantings.

Mulching Around Trees

1) Plant tree.

2) Amend soil around tree in a wide ring shape from a few centimeters from trunk out to 1 meter (3 feet) with a light layer of nitrogen fertilizer, such as chicken manure, and other amendments if necessary. Rake or water in.

3) Spread a layer of permeable weed barrier around the tree in a ring shape, leaving about 15 cm (6 inches) diameter around the trunk of the tree for it to "breathe." Make certain there are no gaps in the ring shape through which weeds can emerge. Water the weed barrier layer thoroughly before the next step.

4) Spread compost and/or mulch about 15 cm (6 inches) thick over the weed barrier, again making sure it is several centimeters away from the trunk of the plant.

The Ongoing Process

To make mulching as efficient and easy as possible, use mulch materials which are readily available. With good planning, mulching of gardens and orchards can become a regular part of maintenance-just mulch with handy materials such as grass clippings, plant prunings (chipped or roughly chopped), animal bedding, etc.. Eventually, other tasks such as watering, fertilization and weeding will be reduced. The overall maintenance burden in mulched conditions, when properly executed, is far less than in conventional systems.

Once a plant is properly mulched, its own leaf drop will constantly add to that mulch. But is natural leaf drop enough to maintain the mulch? The answer to this depends on the plant species and also how the plant is growing in relation to other plants. Certain trees produce tremendous amounts of leaf matter which decomposes rather slowly; examples are: avocado, macadamia, lychee, as well as many others. These trees can be expected to generate sufficient mulch for themselves once vigorous growth is attained. Unfortunately, under most conditions many trees do not create enough long lasting mulch for maintenance of their needs. To explain this apparent deficiency, look once again at the forest. Here, plants are "stacked" in the vertical direction in ground-level, middle, and tall vegetation. This means that the ground under each plant receives organic matter from several plants.

There are many ways to produce sufficient mulch at your site. Grass clippings, for example, represent nutrient rich mulch material. Deep rooted, vigorous growing plants that readily come back from hard pruning or coppicing will also work. There are several nitrogen fixing trees which produce copious amounts of green matter. Each should be evaluated for the specific site before planting. Other plants that work well are kukui, hau, desmodium,, various bunch grasses (such as Guinea grass), lemon grass, comfrey, etc.. Also, many water plants such as water hyacinth are good mulch materials. Since plants that produce heavy amounts of organic matter are by their nature nearly irrepressible, extreme caution should be taken not to let these plants escape your management and become weedy.

Sheet mulching should not be confused with composting, artificial weed barriers, or green manuring. Sheet mulching as described here is quite different from these in that it seeks to recreate the organic mulch layer of the forest with a minimum of effort from people. Properly planned, a backyard or orchard system will produce its own raw mulch in sufficient amounts and people are involved only in putting this material back onto the ground where it belongs.

References and further reading:

• Molly Curry's article, "Sheet Mulch Now!" in The Permaculture Activist, issue No. 34-A, August 1996. Order from The Permaculture Activist, P.O. Box 1209, Black Mountain, NC, 28711, USA.
• Bill Mollison's excellent Permaculture: A Practical Guide for a Sustainable Future, published by Ten Speed Press and available from bookstores.
• ECHO's informative, THICK MULCH FOR NO-TILL GARDENS
• Ruth Stout's No Work Gardening Book, published by Rodale Press, is an excellent reference but out-of-print and hard to find.

Author Contact:

by Craig Elevitch and Kim Wilkinson
Permanent Agriculture Resources
PO Box 428, Holualoa, Hawaii 96725 USA
www.agroforestry.net

© 1998

The Hawai‘i Island Homegrown: Start-up guide for an organic self-reliance garden

A new publication of the Hawai‘i County Resource Center, a program of the County of Hawai‘i Department of Research and Development. This well-illustrated introduction to organic gardening on Hawai'i Island is an excellent resource for any beginning gardener. The guide includes lists of resources and web links for each topic covered.
(2.1MB PDF)

Nitrogen Fixing Tree Start-up Guide

This comprehensive 12-page guide introduces nitrogen fixing trees and their products and uses in tropical agroforestry. Extensive charts for species selection are included.
(388KB PDF)

A Guide to Orchard Alley Cropping–for fertility, mulch and soil conservation

This 10-page guide explains how the practice of alley cropping can provide an on-site resource for mulch and soil fertility. Includes step-by-step instructions on designing an alley cropping system with tree crops.
(393KB PDF)

Can I Grow a Complete Diet? Designing a Tropical Subsistence Garden

This article presents a framework for growing a complete diet in a tropical homegarden. It includes an example species list.
(170KB PDF)

The potential of chainsaw milling outside forests

This comprehensive article covers developments in small-scale chainsaw milling for farms, ranches, and urban lots.
(249KB PDF)

Deep pipe irrigation

An introduction to a very effective, low-tech irrigation method especially applicable to dryland environments.
(500KB PDF)

Leaves to Live By: Perennial Leaf Vegetables

There are numerous tropical perennial trees and shrubs with highly nutritious edible leaves. Such plants can form the foundation of a highly productive, low maintenance garden. 
(135KB PDF)

Trees on farm to mitigate the effects of HIV/AIDS in SSA

Describes how agrobiodiversity, including trees, in farming systems plays a modest but nevertheless valuable role in HIV/AIDS mitigation. by Ard Lengkeek.
(213KB PDF) 

Download Adobe Acrobat Free reader

If You Can't Eat Them, Succeed Them!

How to get started in this thick mat of weedy trees? What to do about all the huge clumping grasses in the pineapple patch? How to manage this morning glory vine strangling the orchard? I have had a lot of questions come up in the course of working in permaculture in Hawai'i, for myself on my own projects and from people I meet who are working toward sustainability. Whenever I get myself into a muddle about how to handle weeds, I remember my weed motto: If You Can't Eat Them, Succeed Them!

The function of weeds on the farm

First of all, I have to keep in mind that if I am starting to worry about weeds, it is usually because the weeds are outrunning me, or running me over, on the road to farm improvement. After all, weeds take farm land in the same direction I want it to go: towards more diversity, resilience, and abundance. For example:

Weeds support diverse soil microlife

Soil microlife feeds off plants. The diversity of plants on the surface is directly related to the diversity of microflora in the soil. Weeds can contribute greatly to that diversity. Removal of weeds to bare the soil reduces diversity. It is very likely that there is important soil life or function being supported by some family of weed that has yet to be documented.

Weeds control erosion and conserve water

Bare ground loses moisture to the air on sunny days, and soil to erosion when it rains. A healthy groundcover of living plants will conserve moisture and prevent erosion, and weeds can be part of that groundcover.

Weeds provide insect habitat, and encourage birds

Butterflies, spiders, bees, dragonflies, praying mantis, ladybugs, and other insects need food and habitat to thrive. A variety of insects will also support birds. A healthy mix of insects encourages balance and reduces the chance of insect "problems."

Weeds are a source of food and medicine for people

Many plants that I used to think of as weeds are prized as nutrient-rich vegetables or medicinals all over the tropics. A few examples in Hawai'i (all escaped introduced species) include amaranth, portulaca, bitter melon, chayote, Spanish needle and gotu kola. Many of these tolerate drought or other harsh conditions far better than cultivated vegetables, and can be quite delicious.

Weeds provide food for crop plants

In the tropics, nutrients essential to crop plant health are primarily in organic matter, not bound up in the soil. Organic matter needs to cycle through the soil for nutrients to get to plants. Cutting weeds back and mulching plantings with them is a common practice with tropical farmers, and increases crop plant health. It is best to cut the weeds before they seed to keep the seeds from sprouting right next to the crop. Weeds also can be soaked in water in a covered container for about a week then fed to plants in a (smelly!) nutrient-rich liquid fertilizer tea.

Weeds are a source of food for animals

Animals can be integrated in the farm to do most of the weed resource management. For example, ducks are used for selective weed control, because they can often be trained as ducklings to develop a taste for some weeds, and will eat those first when allowed to range freely.

Succeed the weeds

So, having reminded myself that weeds are useful, particularly as food for soil life, people, animals, and plants, I can use them as a resource. But, what about when it looks like the weeds are eating the crop plants, and not the other way around? If I have a particularly vigorous weed enthusiastically encroaching on a plant I desire (for example, a bunch grass surrounding a young citrus tree and suppressing its growth), there is one thing I can do, short of abandoning my planting: play the weed's game. The name of the game is succession. I have to be more appropriate than the weed, and make the weed's job obsolete. In short, I succeed the weed.

The weeds are taking the land the same direction I want it to go, towards more diversity, stability, and abundance. It is counterproductive to focus on fighting weeds, since after all they have the land's best interest at heart. Besides, I can't win. They have been excelling in the process of succession for many more generations than I have.

In the natural process of succession, weeds establish where they find a place, usually in open or partially open conditions, especially on bare soil. They modify the environment, eventually making the area inhospitable (too shady, etc.) to more of their kind. Other plants come in who thrive in the modified conditions, and the process of succession continues until the ecosystem is more or less stable, usually culminating in a closed-canopy forest. Most of the plants that I call weeds are involved in the primary stages of natural succession. They are medicine for the soil, repairing it and revitalizing life.

Succeeding weeds is about stepping-up the process of succession. I don't try to stop or arrest the process the weed is involved in; I speed it up. For example, introducing fast-growing trees like nitrogen fixing trees can alter the environment, making groundlayer weed growth slow or even stop with shade. Filling the space with the trees and plants I want will leave less room for weeds. Some of the most aggressive weeds need full sun and low fertility to thrive; by increasing shade, organic matter and soil health they will disappear.

As a last resort, or in areas where the weeds are just too overwhelming, I may need to take a step back in the succession process. This may involve sheet mulching with a thick weed barrier once, baring the soil once, or even spraying herbicide to kill grasses one time. But I have to remember that this is a step back from the natural process of things, and the next step is the weed's turn. Unless I want to be involved in a tedious two-step (I remove weeds, they come back, I remove weeds, they come back) for the rest of my farming career, I need to take two steps forward immediately after taking the one step back. This means mulching and filling the space with appropriate plants (groundcovers, crop trees and other vegetation), creating a healthy system with no room and no need for voracious weeds to modify it. Using this approach in the case of the citrus tree, I hand-pull, smother, or herbicide the bunch grass once, mulch the tree, then introduce a living groundcover vine to fill the area where the grass was encroaching. I could at the same time interplant with shade trees, as citrus like a little shade and grass does not. Farming in the tropics does not need to be a routine; it can be an evolution, an upward spiral. That is how I know I'm doing it right; when it is easier for me with each passing season.

Take the weed's lead

When choosing plants and methods to succeed the weeds, I take my cues of what is needed and wanted on the land from the weeds themselves. Weeds are experts in the process of succession, and great soil indicators as well, so I always look to them to learn what is appropriate. By imitating and accelerating what the weeds are doing, everyone succeeds.

References and further reading:

• Pfeiffer, Ehrenfried E. Weeds and What They Tell. Bio-Dynamic Farming and Gardening Association, Inc. P.O. Box 550, Kimberton, PA 19442 USA.
• Facciola, Stephen. Cornucopia: A Source Book of Edible Plants. 1990. Kampong Publications, 1870 Sunrise Drive, Vista, CA 92084 USA.

Author Contact:

Kim Wilkinson and Craig Elevitch
AgroForester
PO Box 428, Holualoa, HI 96725 USA
Tel: 808-324-4427, Fax: 808-324-4129
www.agroforestry.net

Copyright 1998

In (re)afforestation work we usually talk about the planting of trees. Lots of 'em. But there's a fundamental limitation in this ethic that planting trees is what we need to save the planet. We should be rather talking about planting forests. Until our planting site has in it the components of the Mother of all plantations - the climax forest system - the "trees" we plant will always be weak and prone to exposure, disease and drought. Could this be why in America the U.S. Department of Agriculture accepts an 85% mortality rate in its plantations on clear fell sites over 100 Ha?

Guilds and Diversity

This is illustrated by a tale of connections in the North American Pacific Coast Forests, between Douglas fir (Pseudotsuga mensezii), soil mycorrhizae and a certain Red Tree Vole. The vole was found to transport spores of the mycorrhizae, needed by the fir for its uptake of soil nutrients within the soil of these forests. On clearfell sites, the habitat of the vole was destroyed and thus it would disappear. As a result, survival of fir seedlings was severely reduced. These components survive together and benefit each other in a symbiotic association known in Permaculture circles as guilds. In design, we work to create guilds, or rather to place the right species in such a way that they can create themselves. This illustrates the importance of diversity in our plantations.

Soil life

Thus we are not just looking at planting trees, but accommodating the soil life which is the foundation of healthy biological systems, be they forests, wetlands or prairie grasslands. In one gramme of undisturbed forest soil there may be 1000 million bacteria. These are the life, the very creators of the soil and thus everything that grows upon it. They give the "productive capacity" of our soil. Roots of plants growing in undisturbed soils form associations with the soil microorganisms - the latter make nutrients available for the former, and the microorganisms gain carbon in particular. Up to 80% of Carbon fixed in photosynthesis goes into below ground processes. While this carbon is "lost" to the plant, it is not lost to the system, of which the plant is only a part. The soil organisms improve plant growth through effects on nutrient cycling, pathogens, soil aeration and water holding capacity. Giving priority to feeding and supporting the life in the soil makes caring for plants growing there a much easier task.

Succession

A further lesson from Nature we would be wise to apply is the principle of succession - the redevelopment of the climax system following disturbance. In forests, this may occur naturally in landslides or the toppling of aged trees, creating clearings in the forests. The human causes are well known - clearfell, livestock pressure, etc. In either situation, if allowed, Nature will re-colonise sites using biological systems specifically adapted to the situation. If soil is poor and soil moisture low, She will establish plants which can survive. These can be called "pioneer" ground covers, followed by pioneer shrubs and trees. Often they are nitrogen-fixing legumes, able to synthesize nutrients from the air when they're not available in the soil. Such plants have the chief purpose of preparing the ground for the next stage - covering and protecting the soil, giving natural water and nutrient cycles a jump-start, and thus giving species which would not otherwise have survived a suitable niche in which to thrive. This process continues, each stage leading to a more fertile one, where the ability for a greater range and diversity of species to thrive increases until the climax state is reached once more. Throughout this process the annidated nature of the system becomes evident, with multi-storey "stacking" producing crops and system yields in a vertical plane as well as the "conventional" horizontal system (as with mono-crops).

Limiting Factors

For vital growth of biological systems, such processes and conditions are dependent on a few crucial factors mainly in the soil surface areas - moisture, air (oxygen), organic matter, temperature, the presence of symbiotic relationships (Friends), etc. When any one of these factors is sub-optimal or missing, growth is impaired even if other needs are in abundance. All the irrigation in the world will not produce an orchard if there is no fertility in the soil, and vice-versa.

Total Yield

Medicinal herbs, spices, dyes, fibre plants, bee forage plants, root crops and wildlife habitat are all part of the total yield. In forestry often these "Non-Timber Forest Products" (NTFPs - thankfully they're not called "minor forest products" anymore) are ignored - especially when we're not treating our planting site as a complete ecological system.

Implication for design - in imitation of nature

So the simple planting of trees is thus changed to creating, or allowing, complex interactions based on what happens naturally. We design to imitate this because it's efficient - nature does it using only sunlight - and successful. Design is also about reducing the limiting factors for optimum productivity.

"Permaculture" is the direct application of the principles of ecology.

(Nature) in the design of sustainable human habitats.

Our designs need to incorporate as many as possible of the above principles when looking at forest plantations. We have a series of design options, for which we need to understand factors such as:

• natural characteristics of the plant species
• niches in time & space the plant occupies - is it a pioneer, shade loving, drought tolerant, fast to establish, light demanding, frost tolerant, etc
• size of the plant above and below ground (wide canopy, deep tap root, etc)
• companions to the plant - birds, insects, other plants, etc.
• human-used products of the plant

When we have an idea of such criteria, we select and place the elements to work together, satisfying human and ecological needs of the site.

Plants that integrate into complete forest systems:

We can then fit additional functions in and around our plantation with the following examples:

The conventional method of mono-crop planting at 2.5m spacing ignores all the opportunities of working with the diversity, succession and stacking principles of natural systems. Similarly, to plant climax-type trees at such spacing can be a waste when they'll need selecting anyway. The above design template allows for diversity, succession, stacking, rapid covering of the ground and quick production too. The latter is important for example when farmers are foregoing grazing needs by protecting the site - but within three to six months fodder can be harvested from the developing understorey. We certainly don't need to be afraid of over planting. Research shows that Gliricidia sepium can reach densities of up to forty thousand trees per Hectare (i.e. 50cm distance between plants) before biomass production is reduced.

Practical Planting

Experiments in Britain, North America and Nepal have illustrated the principle of needing to plant the system, not just the tree. Plantations where a couple of handfuls of forest soil (especially when from a mature tree of the same species) were placed in the pit in the root zone have showed over 50% better survival than those with no inoculant.

Options

This design is only used to illustrate the principles, however. There are countless ways of adapting the design according to needs of the site and user group.

Where sites are very poor or if the right planting materials, time, or labour is in short supply, then the establishment does not have to happen at the same time. We can start by broadcasting the pioneers, such as Artemisia, Sesbania, Crotolaria, Cassia, etc. and next year, following cut-and-mulching of these, establish the next layer. Eventually, the most valuable, long lasting climax species (which you've been growing yourselves in a local nursery in the meantime, of course) can be added.

Any tree species planted as seedlings will benefit from a nurse crop of pioneer/green manure/legume-type plants sown close around. We have used Sesbania, Crotolaria, and Cassia to do this - they grow quick (and will self-seed), so providing shelter on exposed sites (or a sun trap if planted in an arc open to the sun-side where sunlight is in short supply), as well as fixing nitrogen, and bump-starting the soil life processes.

The design can vary in terms of products over horizontal and vertical planes, for example layers of fruit at all levels (vertically), or clumps of fruit at mid-canopy level, fodder at ground level, timber trees at upper canopy level, etc. We can play with succession by cutting (thinning) to maintain clearings at ground level, thus a high degree of edge diversity around the clearing. So design varies as succession continues.

Agroforestry

Contour planting on bunds within cultivated fields (e.g. LEISA - low external input sustainable agriculture ; SALT - sloping agricultural land technology) are not excluded from such applications. The design is rather squashed into contour lines, horizontal planting distances can be reduced to leave up/down slope space for annual cropping systems.

Complexity, not Complications

So if you think this is getting complicated, imagine varying all these dimensions (horizontal, vertical, time and relationships) at once! This is the traditional way of forest farming - the Cavite (Philippines), Chagga (Tanzania), the Western Ghats (Goa, India) are living examples. In Western Nepal, the Raute (meaning "Lords of the jungle"), nomadic hunter-gatherers on the verge of extinction take it a step further - they just wander through natural forests, gathering what they need and not returning for up to nine years. They don't even have to plant!

Which just leaves one option, to merely protect a site and allow nature to do the rest. However, the above design principles allow us to create intensely productive systems for humans, thus taking the pressure off damaged forest areas, allowing them to exist for their own intrinsic value, and for the health of the Earth.

Teaching method

The principles and variations of plantation and agroforestry design are limited when taught in two dimensions. A fun way is to use an earth pile, and sticks of different length and thickness, from tall, thick sticks (climax trees) to short pieces of straw (ground cover layer). Students can mould landscapes according to their own situations.

References:

• Hart, Robert (1991) "Forest Gardening" Green Books
• Perry, D.A., & Amaranthus, M.P. (1987) "The Use of Mycorrhizal Fungi and Associated Organisms in Forest Restoration" In "Restoring the Earth"

Author Contact:

Chris Evans, Technical Advisor,
Jajarkot Permaculture Programme
c/o P.O.Box 10908,
Kathmandu, NEPAL
Fax +977 1 259833
email jpp@mos.com.np

Copyright 1998 All Rights Reserved

Diverse, productive landscapes such as this have been removed to make way for cash crops. (photo: C. Elevitch)

Pacific Islanders were once among the most self-sufficient and well-nourished peoples in the world, building their agricultural systems around a diverse base of local tree species. As traditional tree-based agroforestry systems were cut down and replaced with cash crops from colonial times onward, much of the knowledge of local tree species and their many products and uses has been lost. At the same time, the conservation benefits of the trees were also lost. There is now a critical shortage of information about local tree species and their applications in sustainable economic development, resource conservation, and food security.

Protection and planting of these species is critical to supporting the genetic, species, and ecosystem diversity of the region. At the same time, native and traditional trees are essential in meeting human needs in sustainable agriculture and economic development. Agroforestry is a vital aspect of sustainable agriculture in the Pacific. Farmers, ranchers, landholders, and producers increasingly require information on tree species to use for windbreaks, crop shade, soil improvement, water conservation, ornamental uses, livestock fodder, potential niche crops, and other applications. Integrating trees can diversify products and enhance the economic and ecological viability of farm systems. Producers are seeking trees to support and protect crops including tropical fruits, coffee, root crops, medicinals, and livestock.

However, efforts to conserve and plant native trees across the landscape are hamstrung by a shortage of information on native and local tree species. Instead, producers and extension agents are often forced to turn to newly introduced exotic species whose applications and products are well-documented in international literature. Many of these exotics are often untested in the region, unfamiliar to local growers, and difficult to acquire. Emphasizing exotics also poses serious threats to Pacific Island ecosystems through the introduction of potentially invasive plants.

Extension agents in the Pacific Islands stressed in interviews that public interest in agroforestry and tree crops is high or increasing, but needed information on tree species for the region is very scarce. What little information is available is mostly scattered amongst obscure references, mainly of a botanical nature. These fail to provide the kind of detail producers and land users need to make informed decisions about integrating local tree species effectively.

The Traditional Tree Initiative will provide vital information needed to advance sustainable agriculture and economic development while protecting genetic and species diversity. By expanding the planting and conservation of native and traditional trees across the landscape, the Traditional Tree Initiative will:

• Support sustainable agriculture through the promotion of time-tested, locally-appropriate trees for windbreaks, soil conservation, crop shade etc.
• Strengthen traditional tree-based land use practices
• Promote sustainable economic development by providing information on underutilized species and their potential crops
• Enhance the diversity of products and species on agricultural land
• Protect and expand wildlife habitat in agricultural and residential zones
• Enhance knowledge of how to use tree resources sustainably
• Protect the unique culture and ecology of the region
• Counter risks of bioinvasions from introduced exotics by promoting local species
• Conserve the genetic wealth and species diversity of the region by integrating native trees with production

See available species profiles

This project will meet the needs of extension agents, producers, and land users by creating a concise, practical, user-friendly information resource for traditional Pacific Island tree species. Traditional Tree Initiative will produce a series of 6–12 page fact sheets covering fifty of the most important species in the region. Each fact sheet will provide detailed, practical information on products, uses, interplanting applications, environmental requirements, and propagation methods. The fact sheets will be freely available in electronic form via the internet, both in HTML and PDF formats. The fact sheets will also be disseminated in reproducible form and as a searchable CD (with live internet links) to 200 agricultural offices, libraries, and schools in the region

Twenty experts in Pacific Island agroforestry are authoring the species fact sheets, representing expertise from throughout the Pacific. In addition, a panel of fifteen extension agents, producers and other professionals will review the species profiles. Many others will give feedback through an innovative e-mail review process.

Download
Agroforestry Guides for
Pacific Islands

The Project Coordinators have been educators in and practitioners of Pacific Island agroforestry since 1990. Their field experience in a variety of environments coupled with their longstanding commitment to agroforestry extension makes them uniquely qualified to coordinate this project. They recently produced the USDA/SARE-funded publication, Agroforestry Guides for Pacific Islands, which provides planning information for a number of agroforestry practices. They also publish The Overstory, an electronic information resource for reforestation, conservation, and agroforestry, with subscribers in over 170 countries. The Traditional Tree Initiative’s species fact sheets will be a unique and vital resource for sustainable development in the Pacific Islands.

A solid foundation of locally appropriate, time-tested tree species is essential to sustainable land use in the Pacific Islands. Promoting a diverse array of proven native and traditional species will support the conservation of the unique culture and ecology of the region, instead of threatening these with new and risky introductions. The Traditional Tree Initiative will put vital information for the conservation and expansion of Pacific Island trees at the fingertips of the people who need it most.

Sponsorship

Species Profiles for Pacific Island Agroforestry are distributed by agroforestry.net with support from: 

• U.S. Department of Agriculture’s Western Region Sustainable Agriculture Research and Education (WSARE) Program;
• SPC/GTZ Pacific-German Regional Forestry Project;
• USDA Natural Resources Conservation Service (USDA NRCS);
• State of Hawai‘i Department of Land & Natural Resources Division of Forestry & Wildlife;
• USDA Forest Service Forest Lands Enhancement Program;
• Kaulunani, an Urban Forestry Program of the Hawai'i DLNR Division of Forestry & Wildlife
• USDA Forest Service; 
• Muriel and Kent Lighter

Selected References

• Elevitch, Craig. 1996. Working Trees: Enriching Your Farm with Useful Trees, Holualoa, Hawaii.
• Glover, Nancy. Profiles of Select Nitrogen Fixing Trees for Small Farm Planting. NFTA, Waimanalo, Hawaii.
• International Institute of Rural Reconstruction. 1990. Agroforestry Technology Information Kit, IIRR, New York, New York.
• Macklin, Bill et al. 1989. Establishment Guide. NFTA Cooperative Planting Program NFTA, Hawaii.
• Nitrogen Fixing Tree Association. 1989-1994. NFT Highlights. Nitrogen Fixing Tree Association, Morrilton, Arkansas, USA.
• Tripathi, Bansh R. et al. 1992. Alley Farming Training Manual, Volume I: Core Course in Alley Farming, Ibadan, Nigeria.

Many traditional Pacific island crops such as taro provide food for local consumption as well as potentially high-value commercial products. Above, taro in Hanalei Valley.

Collaborators

Dr. J. B. Friday

UH Extension Specialist in Forestry, Department of Natural Resources and Environmental Management, CTAHR, University of Hawai'i, Hilo. He works with landowners, tree farmers, and professional foresters throughout the state on management of both native forests and tree farms. His particular interests are in restoration of native forests, silviculture of koa, agroforestry, and management of high value plantation timber species.

John H. (Bart) Lawrence

Asst. Director for Operations, Pacific Islands-West with the USDA Natural Resources Conservation Service, Guam office. He provides support and assistance to Pacific Basin NRCS Field Offices regarding natural resource-related issues and conservation projects. His responsibilities also include providing Conservation Technical leadership and direction in developing conservation technical materials for the U.S.-affiliated NRCS Field Office Technical Guides.

Dr. Roger Leakey 

Professor of Agroecology and Director of the Agroforestry and Novel Crops Unit, School of Tropical Biology, James Cook University in the wet tropics of Queensland, Australia. Between 1993-97 he was Director of Research at ICRAF (formerly the World Agroforestry Centre). He has undertaken studies on tree domestication, genetic improvement of tropical trees, agroforestry in dry and moist tropics, soil microbiology, vegetative propagation, with research projects in Kenya, Cameroon, Ghana, Nigeria, South Africa, Namibia, Costa Rica, Indonesia, Malaysia, Papua New Guinea, Vanuatu and Solomon Islands. Since 1982, he has undertaken consultancies for ODA, World Bank, European Development Fund, FAO and ACIAR, in Malaysia, Thailand, Vietnam, Laos, Japan, Philippines, India, Bolivia, Costa Rica, ten countries of West Africa, and Australia.

Dr. Diane Ragone

Director of the Breadfruit Institute at the National Tropical Botanical Garden on Kaua'i. Her research interests include documenting the history and status of economic plant introductions and crop plant collections in the Pacific islands. Dr. Ragone has worked extensively throughout Oceania for more than 20 years to collect cultivars of important crops and document their traditional uses and related cultural practices. She is developing the Breadfruit Institute as an international center to conserve breadfruit diversity and traditional knowledge and to promote its use for nutrition, income, and environmental protection.

Noni expert Dr. Scot Nelson examines trees at Sweet Spirit Farms, Hawai'i. Noni is a model high-value crop that is native to certain Pacific islands and was introduced centuries ago by indigenous peoples throughout the Pacific.

Advisors

Rogerene (Kali) Arce 

An extension agent with the University of Hawai'i at Manoa Department of Tropical Plant and Soil Sciences, Moloka'i Extension Office. She has worked extensively with farmers to improve on-farm income generation, particularly with Hawaiian Homesteaders.

Nicklos (Nick) Dudley

Forester at Hawai'i Agriculture Research Center (HARC) in Aiea, O'ahu. He specializes in silviculture, selection and breeding, and seed production.

Robert J. Joy

Plant Materials Specialist with the Natural Resources Conservation Service (NRCS) in Ho'olehua, Moloka'i. He provides technical guidance in the use of plant materials and is responsible for carrying out systematic selection, evaluation, and improvement of plants used in soil and water conservation in the Pacific.

Kelly Lange

Educational Program Director and Certification Coordinator for the Hawai'i Organic Farmers Association in Hilo, Hawai'i. She works directly with the 200+ certified organic farms in Hawai'i and coordinates workshops.

Ken Love 

A specialist in tropical fruit cultivation and marketing, in Kona, Hawai'i. He currently promotes farm product diversification programs based on seasonality in order to spread the need for labor.

Dr. Mari Marutani

Professor of Horticulture, University of Guam. She specializes in germplasm improvement, conservation of native species, and agroecology.

Dr. Scot C. Nelson 

A plant pathologist with the University of Hawai'i at Manoa College of Tropical Agriculture and Human Resources, based in Hilo, Hawai'i. Scot works with diseases of tropical crops and fruits as well as a wide variety of native plants.

Dr. William Raynor 

Director of the The Nature Conservancy (TNC) Micronesia Program, based in Pohnpei. He oversees the TNC conservation programs in five Pacific island nations.

Dr. Francis Zee 

Supervisory Research Horticulturist at the USDA Agricultural Research Service, Hilo, Hawai'i. His responsibilities are to collect, identify, evaluate, maintain, utilize, preserve, and distribute important clonal germplasm for designated tropical fruit, nut, beverage, and ornamental crops.

High-value crops such as tea may capture unique markets by being grown in pristine Pacific island environments. Eva Lee displays a bottle of tea syrup, one of many specialty products that extend tea products into new markets.

Coordinator

Craig Elevitch

Director of Permanent Agriculture Resources and Project Coordinator, responsible for all aspects of planning, coordination, and logistics. Since 1989, he has worked in agroforestry design, management, and education. His projects focus on multipurpose trees that have economic, environmental, and cultural significance. He also directs Agroforestry Net, a nonprofit educational organization dedicated to empowering people in agroforestry and ecological resource management. The organization's internationally recognized publications have guided thousands of readers in developing agroforestry systems, ecological restoration, and reforestation on farms, ranches, homegardens, and conservation areas. Publications include Agroforestry Guides for Pacific Islands (2000), Growing Koa: A Hawaiian Legacy Tree (2003), Traditional Trees of Pacific Islands: Their Culture, Environment, and Use (2006), Noni: The Complete Guide for Consumers and Growers (2006), and Pathways to Abundant Gardens: A Pictorial Guide to Successful Organic Growing (2007).