Crop Management and Conservation Factors of the USLE for Tea in the Nilgiris

Growing of tea on sloping land without any soil and water conservation measures causes enormous soil loss in the initial years. Therefore a field experiment was conducted to evaluate the performance of different conservation measures viz., Contour staggered trenching (CST), cover crop of beans and CST + beans on runoff and soil loss in new tea (Commellia sinensis) plantations in the Nilgiris. Average soil loss for seven years was minimum in contour staggered trenching (CST) (0.93 t ha⁻¹ year⁻¹) followed by CST + beans (1.02 t ha⁻¹ year⁻¹) and cover crop of beans alone (1.95 t ha⁻¹ year⁻¹) as against 2.84 t ha⁻¹ year^−l from the control. The crop management factor (C) of tea and conservation factor (P) for different conservation measures for use in the universal soil loss equation (USLE) were estimated. Based on the canopy development, the growing period of tea was divided into three stages viz., initial stage (1^st year), establishing stage (2^nd to 4^th year) and established stage (5^th year onwards). The average values of crop management factor for initial stage, establishing stage and established stage were found to be 0.193, 0.0267 and 0.0163, respectively. The average value of conservation factor for CST, cover crop of beans and CST + beans were found to be 0.39, 0.38 and 0.69, respectively.