Land Suitability Evaluation and Management of Ultisols for Some Tree Crops Cultivation in South South Nigeria.

A rigid grid soil survey was done on 115.5 hectares of land in Ultisols of South Southern Nigeria at a detailed scale to evaluate its suitability for the cultivation of some tree crops (Cocoa, Plantain, Cashew, Pawpaw and citrus). Mapping units were delineated on the basis of morphological characteristics examined at 100 m along traverses which were cut at intervals of 100 m from a predetermined baseline. The soils were classified according to local series and USDA soil taxonomy. Four mapping units were delineated and represented by a pedon. All the pedons were classified as Ultisols. Land suitability evaluation showed that all the pedons (115.5ha) were marginally suitable for Cocoa cultivation due to limitations in climate; pedons 1(19.4ha) and 4 (50.3ha) were marginally suitable for plantain cultivation due to limitations in fertility, while pedons 2(18.3) and 3(27.5ha) were moderately suitable for plantain cultivation due to limitation in climate. Pedon 1 was currently not suitable for citrus, pawpaw and cashew due to limitations in fertility; pedons 2, 3 and 4 were marginally suitable for citrus pawpaw and cashew due to limitations in climate and fertility characteristics. Amendment with organic fertilizers is recommended for the cultivation of Citrus and Plantain. However, the other crops may only be cultivated when there is enough economic justification