Agroforestry Chapter 1 (Part 1): Introduction, History, Definitions and Potential
Agroforestry Notes · Chapter 1 · Part 1
Chapter 1 (Part 1): Introduction to Agroforestry
Concept, history and institutionalisation, all standard definitions word for word, basic ideas, objectives, attributes and the potential of agroforestry.
1. Concept: a new name for an old practice
Growing trees together with crops and animals on the same land is as old as farming itself. What is new is the name, the science and the institutions. That is why agroforestry is called “a new name for an old practice”. The word joins agriculture and forestry, and the subject sits at the interface of the two.
Agroforestry is a collective name for land-use systems in which woody perennials (trees, shrubs, palms, bamboos) are grown with agricultural crops and/or animals on the same unit of land. It combines the production of several outputs with the protection of the resource base, which is what sets it apart from simple intercropping.
Food, fodder, fuel, timber, fruit and cash from the same plot, spread over the year and over many years.
Trees check erosion, add organic matter, recycle nutrients and moderate the microclimate.
Stresses many local multipurpose trees and shrubs rather than one exotic crop.
Especially suited to small farmers, marginal lands and fragile environments of the tropics.
More than any other land use, it depends on local culture, tenure and farmers’ choices.
Structurally and functionally more complex than monocropping: at least two plant species, one woody, interacting.
Ancient roots
- India: the text Krishishukti of Maharishi Kashyap classified land and marked areas around houses, wells and tanks for tree planting.
- Europe: until the Middle Ages, degraded forest was clear-felled, burnt, cropped and then replanted with trees (King, 1987). This continued in Finland until the end of the 19th century and in Germany until the 1920s.
- Philippines: the Hanunoo practised a careful shifting cultivation in which useful trees were spared (Conklin, 1957).
- Nigeria: the Yoruba mixed herbs, shrubs and trees to save labour and keep soil fertile.
- Myanmar, 1806: U Pan Hle, a Karen in the Tonze forests of Tharrawaddy, raised teak by the taungya method and showed it to Sir Dietrich Brandis. Taungya became the first organised agroforestry method (see Chapter 3).
2. Why agroforestry rose in the 1970s
Several forces in the 1970s turned the old practice into a recognised science:
| Driver | What happened |
|---|---|
| World Bank policy | President Robert McNamara (1973) put the rural poor at the centre; the Bank issued its Forestry Sector Policy Paper in 1978 (revised 1991). |
| FAO forestry review | A new forestry ADG at FAO (1974) urged land managers to “eschew the false dichotomy between agriculture and forestry” (King, 1979). |
| Intercropping and farming systems research | Interest in mixed cropping showed that combinations often out-yield sole crops. |
| Food crisis and population growth | Need for more food from the same land in the tropics. |
| Tropical deforestation | About 12 Mha/yr (World Bank, 1991); FAO estimated 17.1 Mha/yr for the 1980s. Shifting cultivation caused about 70% of deforestation in tropical Africa (FAO, 1982). |
| Energy crisis | Fuelwood shortage became the “other energy crisis” of the poor. |
| IITA research | IITA, Ibadan (Nigeria) began integrating trees and shrubs with crops (Kang et al., 1981), which led to alley cropping. |
| IDRC project | Canada’s IDRC commissioned John Bene in July 1975 to identify gaps in tropical forestry research. |
From Bene’s report to ICRAF
3. Definitions of agroforestry
Many definitions were proposed between 1977 and 1982. Learn them with author and year. The wording below is quoted exactly from the sources.
Reading the ICAR/ICRAF definition
Trees, shrubs, palms and bamboos. At least one must be present.
The trees are purposely grown or retained, not accidental weeds.
One farm or plot, not a forest next to a farm.
Components may be mixed in space (together) or in time (one after another).
Both ecological and economic; this is what separates agroforestry from simply having trees nearby.
Bjorn Lundgren (then Director General of ICRAF) said a scientific definition must stress two features: the deliberate growing of woody perennials with crops and/or animals, and a significant interaction (positive and/or negative) between the woody and non-woody components.
Some argued that the linguistically correct word is “agriforestry” (Stewart, 1981), but agroforestry was already established. Nair sums up the essence as the purposeful growing or deliberate retention of trees with crops and/or animals in interacting combinations for multiple products or benefits from the same management unit.
| Author (year) | Key words to remember |
|---|---|
| Bene et al. (1977) | Sustainable management, overall production, cultural patterns of local population |
| King and Chandler (1978) | Same unit of land, simultaneously or sequentially, cultural practices |
| Nair (1979) | Scientifically sound, ecologically desirable, practically feasible, socially acceptable |
| Lundgren and Raintree (1982) | Collective name, woody perennials deliberately used, ecological and economical interactions |
4. Basic ideas and objectives
Basic ideas that follow from the definition
Of plants, or plants and animals, at least one of which is woody.
An agroforestry system always gives more than one product or service.
Because a woody perennial is involved, the cycle is always more than one year.
There are both positive and negative interactions among components.
Even the simplest system is more complex, ecologically and economically, than monocropping.
Two essential aims
- The system should conserve and improve the site.
- It should optimise the combined production of trees, crops and animals.
Objectives in practice
- Raise total production per unit area and reduce the risk of crop failure.
- Meet the farm family’s needs for food, fuel, fodder, timber and cash.
- Restore degraded and marginal lands and control erosion.
- Generate employment and reduce pressure on natural forests.
- Improve the microclimate and soil fertility for associated crops.
5. Attributes of agroforestry systems
All agroforestry systems are expected to have three attributes. They are also the yardsticks used to evaluate systems (Chapter 6).
| Attribute | Meaning | How agroforestry achieves it |
|---|---|---|
| Productivity | Maintain or increase production of preferred commodities and productivity of the land | More tree products, better yields of associated crops, lower cropping inputs, higher labour efficiency |
| Sustainability | Conserve the production potential of the resource base | Mainly through the beneficial effects of woody perennials on soil: litter, nutrient cycling, erosion control |
| Adoptability | The technology must be accepted by farmers | New technologies must fit local farming practices and social conditions |
6. Potential of agroforestry
The e-course lists the following ways agroforestry can help people and the land.
N-fixation, nutrients pumped up by deep roots, higher CEC and organic matter, and mycorrhizae raise crop yields.
Better moisture retention, regulated stream flow, drainage of waterlogged or saline soils by water-loving trees.
Firewood, pyrolysis products (charcoal, oil, gas), ethanol from carbohydrate-rich fruits, oils, latex and resins.
Building material, shade, windbreaks, shelterbelts and live fences.
Pulp, tannins, essential oils, medicines, wood for implements and fibre for weaving.
Sale of tree products, indirect gains from higher yields, more income per unit area than monoculture.
Seed collection, nursery and planting generate about 200–500 man-days of work a year.
India has about 100 Mha of wasteland that can carry trees.
Carbon sequestration in tree biomass and in the soil.
Farm-grown fuel reduces pressure on natural forests and saves women’s time.
Improves physico-chemical properties and soil life.
Improves landscape connectivity and gives habitat to wild species.
Edible products in India come from about 213 tree, 17 palm, 128 shrub, 116 herb, 4 fern and 15 fungus species. Trees also use solar radiation through the whole year, while seasonal crops use it only for part of the year.
| Agroforestry | Monocropping |
|---|---|
| Two or more species, at least one woody | One species |
| Several outputs and services | One main output |
| Cycle more than one year | Usually one season |
| Positive and negative interactions to manage | Only intra-specific competition |
| Lower risk; protects the site | Higher risk; site may degrade |
7. Quick revision box
- New name for an old practice; interface of agriculture and forestry.
- Krishishukti (Maharishi Kashyap): trees around houses, wells and tanks.
- 1806: U Pan Hle, Tharrawaddy (Myanmar), teak taungya, shown to Brandis.
- July 1975: IDRC asks John Bene; report Trees, Food and People (1977).
- ICRAF 1977, Nairobi; renamed 1991; now World Agroforestry Centre.
- Journal Agroforestry Systems from 1982.
- Accepted definition: Lundgren and Raintree (1982).
- Nair (1979): scientifically sound, ecologically desirable, practically feasible, socially acceptable.
- Attributes: productivity, sustainability, adoptability.
- AF cycle is always more than one year; at least one component is woody.
- Edible species in India: 213 trees, 17 palms, 128 shrubs, 116 herbs, 4 ferns, 15 fungi.
8. Interactive MCQ Quiz
15 questions. Tap an option to see the answer and explanation, then go to the next question.
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