Influence of multipurpose trees on agricultural crops in arid regions of Haryana, India

The effects of multipurpose trees on the productivity of agricultural crops were studied in the arid regions of Haryana. In one of the experiments, wheat was grown on irrigated farms having scattered trees of Dalbergia sissoo, Azadirachta indica, Prosopis cineraria and Acacia nilotica. Data of wheat yield for each tree species at different distances (1, 3, 5, and 7 m) and four directions (East, West, North and South) from the tree bases and control (no trees) were collected. Results indicate that Azadirachta indica and Prosopis cineraria did not produce any significant difference in the wheat yield while the other two species (Dalbergia sissoo and Acacia nilotica) gave a reduction in yield. A. nilotica had a more significant and prominent effect and a reduction of 40 to 60 % wheat yield was observed. Dalbergia sissoo reduced yield by 4 to 30 % but the reduction was only up to a distance of 3 m. In general, the impact of trees on productivity was observed up to 3 m distance and there was little, if any, impact up to 5 m and almost no impact at 7 m. In another experiment, D. sissoo (18-years-old) was raised as a windbreak and the productivity of cotton was assessed. The tree belt reduced the wind speed by 15 to 45 %, depending on season and wind speed. The influence of trees on cotton yield was observed to be negative up to 2H (36 m), where H is tree height, i.e. 18 m. Cotton productivity was observed to be maximum between 2H and 5H. Depending upon orientation of tree belt, the increase in cotton yield was found to be 4 to 10 %.