Abstract
Clay soils occupy approximately 50 per cent. of Trinidad's land area. Sugar-cane has been an important crop on some of these soils for many decades and presently occupies 40 000 ha, much of this being heavy clay soils. The properties of six important sugar-cane clay soils (5 Vertisols, 1 Mollisol) are reviewed, stressing the constraints on their management. The six include two soils typical of low-lying basin land, one of river valley bottom-land and three upland Vertisols. The chief constraints observed are the high clay content (54-81 per cent.), which makes tillage difficult and limited to the dry season, causes impeded drainage and gives rise to poor aeration and compaction problems. Some of the soils are also highly acid and show toxic levels of exchangeable Al. The particular feature of the sugar-cane plant and the cropping system are discussed and it is concluded that sugar cane is relatively well adapted to the management of these soils. Some implications of diversifying into other crops on the management of these soils are discussed and some suggestions made on alternative cropping of these soils.
