The Effect of Rainfall and Age on the Yield of Some Unfertilized Fodder Crops in Kenya

Abstract

Five perennial fodder crops and maize were grown for 11 years or more in unfertilized soil. The effect of rainfall, annual and seasonal, and age from planting was examined in detail. Increased rainfall, whether annual or seasonal, led to increased yields of all crops, although the extent of the increase depended on the type of crop, the nature of the rainy season, whether long or short, and in particular the age of the perennial crops. All the perennials aged at similar rates and ageing led to reduced yields. The depressing effect of age is thought to be due to overcrowding and possibly a concealed loss of fertility.