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AGROFORESTRY

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					                                         AGROFORESTRY
        Agroforestry is any sustainable land-use system that maintains or increases total yields
by combining food (annual) crops with perennial crops and/or livestock on the same unit of land,
either alternately or at the same time, using management practices that suit the social and
cultural characteristics of the local people and the economic and ecological conditions of the
area.
        The main objectives of agroforestry are to conserve and improve the site and to
maximize the combined production of forest crops (timber, fuelwood, fruits for food), agricultural
crops (corn, rice, cassava, legumes, and vegetables) and also animal husbandry (cow, carabao,
and goat)
        Trees inter-planted with food crops are able to improve and maintain soil fertility and
therefore sustain productivity in two ways such as by decreasing surface water run-off, nutrient
loss, and soil erosion and also by recycling leached and percolated nutrients and ‘pumping’ new
nutrients to the soil surface where they can be used by food crops.
        Characteristics of an agroforestry system normally involve two or more species of plant
(or plant and animals) at least one of which is a woody perennial and which have two or more
outputs (food and money) and the cycle is always longer than one year.
        The trees play protective roles in agroforestry such as in helping to restore and maintain
fertility of the soil and to prevent excessive soil erosion. The key attributes of agroforestry are to
maintain or enhance productivity (economic benefit), environmental quality (environmental
benefit) and should be acceptable to local farmers communities (social benefits).
        There are many ways in which agroforestry can be done. One of which is the alley or
hedgerow cropping. It involves strips of food crops and trees. The hedgerows are established and
planted with fodder species (e.g. ipil-ipil, kakawate and sambong). These species will serve as
soil anchorage, fertilizer, restoration and for animal feeding.
        One other method used in agroforestry is shifting cultivation. This is characterized by a
rotation of or the use of fields using short periods of cropping and longer fallow periods, and the
land is cleared of forest cover, burned and cultivated.
        These are constraints of pruned-tree leguminous hedgerow like high labor requirements
for establishment and maintenance and limited improvement of farm income. Irregular alley
widths make inter-row tillage using animal traction difficult. There can also be unanticipated soil
fertility problems (competition with annuals, particularly in low phosphorus soils) and poor species
adaptation, crop area loss and lack of suitable planting materials.
        Finally, one solution may be to do the Natural Vegetative filter Strips (NVS). NVS are
narrow live barriers of naturally occurring grasses, herbs and shrubs.


                                                                                 Dennis Vincent M. Ferrer
                                                                                           BS Agriculture