Nutrient Harvest through Pruned Material and whole Tree in Populus deltoides Based Agrisilviculture Systems in Central Punjab

The study was carried out at farmers fields to quantify nutrient harvest through biomass of pruned material of 2, 3, 4, 5 and 6 year old plantations and whole tree of Populus deltoides Bartr. (Poplar). The pruned biomass was 327.4, 426.96, 986.27, 1,234.91 and 1,558.59 kg ha^-1 at 2, 3, 4, 5 and 6 year old plantations respectively. The total biomass of branches, main stem and ischolar_main of poplar at exploitable age was 48,96, 89,144, 94,040 and 12,280 kg/ha, respectively. Nutrient concentration was increased from basal segment to terminal segment of pruned braches and decreased with size of the branches. The nutrient harvest through pruned biomass was 46.32 kg ha^-1 N, 6.92 kg ha^-1 P and 19.93 kg ha^-1 K whereas nutrient loss through whole tree was 652.8 kg ha^-1, 75.84 kg ha^-1 P and 719.84 kg ha^-1 K. As the nutrient is exceeded than annual return, additional doses of fertilizers may be required to maintain soil fertility and productivity of the system.