Studies on Soil and Water Management

 for Small Farmers on Flat Heavy Soils

 in the Caribbean


y L. A. Simpson F.
 Department of Soil Science
The University of the West Indies
 St. Augustine, Trinidad, W.I.


 A survey was done in selected areas with clay soils in
Trinidad and Guyana to gain further insights into the soil and
water management problems on small farms. The survey
showed that many farmers, especially in Guyana, expend large
amounts of energy using hand tools in weed control and land
preparation. Farmers had problems in timing tillage opera-
tions due to the weather, unavailability of equipment and cost


of tillage. The limitations to land preparation, fertility and
water management and weed control are highlighted. The
potential of reduced tillage methods, for soil and water conser-
vation and stable continuous soil productivity, is discussed.
Results of tillage studies in Trinidad and Guyana are sum-
marised. Suggestions for future research to obviate the limita-
tions to increased use of reduced tillage methods are discussed.


 Clay soils are widespread in the Caribbean. They are difficult
to manage under the humid tropical conditions that are ex-
perienced in Guyana and Trinidad. In these countries a large pro-
portion of the soils has been used for the production of sugar
cane, rice and tree crops. Many small farmers occupy these soils
and cultivate mainly food crops. The soils are suitable for rice pro-
duction and techniques have been developed for cultivating
sugar cane. The sugar industry utilizes heavy machinery for land
preparation. A range of tillage implements are used and several
passes are made before the land is ready for planting. Drainage in
the wet season is a problem and the cambered bed (bedding
system of drainage) has traditionally been used. Over the years
the cambered bed is being replaced by the ridge and furrow
system. In Guyana, flood fallowing for periods of six to nine
months has been used as a technique for soil structure improve-
ment and stabilization in sugar cane production. This technique
is, however, suitable only for large scale operations.
 Clay soil management practices which utilize heavy equip-
ment, flood fallowing and perhaps the cambered bed are not
suitable for small farming. Therefore there is a need to develop
techniques of soil management suitable for the small farmers who
are engaged in food crop production. Although reduced tillage
has always been used by the subsistence farmer, e.g., in shifting
cultivation, the trend has been to encourage conventional tillage.
 There has, however, been a reexamination of the suitability of
conventional tillage methods in the tropics (Lal, 1979) in view of
the rapid loss of soil productivity, accelerated soil erosion, and
deterioration of soil structure.
 Johnson et al. (1982) have also expressed the need for custom
prescribed tillage (CPT) by which tillage operations are proposed
on the basis of climate, soil, crop and socioeconomic considera-
tions. Employing similar philosophy, researchers at IITA in
Nigeria and at ICRISAT in India have demonstrated suitable
reduced and improved tillage systems for soil and water conserva-
tion and management in those areas.
 The extreme form of reduced tillage is zero-tillage or no-
tillage. Here the only soil disturbance is that done to plant the
seed. Weeds are controlled by herbicides, and fertilizers and
amendments are placed on the soil surface or in the mulch cover.
Mulch is essential in no-tillage for the conservation of soil, water


VOL. XX-PROCEEDINGS of the CARIBBEAN FOOD CROPS SOCIETY


and fertilizer, the suppression of weeds and the optimization of
soil temperature. There has been little research on reduced tillage
in this region.
 The soil management techniques which are used by small
 farmers have not been documented and a survey was therefore
 conducted to determine their current soil and water management
 practices. The findings were used in developing a research pro-

 gram for all-year crop production for small farmers.
 The survey findings and some of the research results are
 presented in this paper.

 Survey of Current Soil and Water Management Practices
 of Small Farmers
 The survey of 50 small farmers in Trinidad and 23 in Guyana
 was carried out by enumerators using questionnaires. The results
 of the survey revealed the following:

 Tillage
 In Guyana, small farmers either used the traditional hand tools
 (hoe, fork, spade, cutlass) in land tillage and in the formation of
 ridges and furrows, or they made three passes with the plough,
 followed by finishing operations with hand tools.
 In Trinidad, land preparation was mainly done by contractors.
The tillage implement combinations varied with the crop and soil
type. Disc ploughing, followed by one or two passes with the
rototiller, was the most common practice. Farmers owning trac-
tors used them mainly for transport. Animal drawn implements
and hand tractors were not widely used.
 In both territories, the main limitations in land preparations
were: unavailability of equipment at critical times, timing of
operations, and the high cost of land preparation (estimated in
1982 to be about US$400/ha to brushcut, disc-plough, rototill
and ridge).
 In Guyana, in particular, farmers lacked the financial resources
for these operations and this limited the area of land that was
prepared annually.

Weed Control
 Weed control prior to tillage was generally by brushcutting,
hand weeding and burning. In Trinidad, brushcutting and


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J. I. Lindsa)


A. Gumbs