Search Results
No reduction in yield and quality of pecan nuts or leaf mineral nutrient concentration occurred when 100 lb/acre of N was applied through a drip-irrigation system compared with 200 lb/acre applied either all broadcast or half broadcast and half fertigated. Yield of `Stuart', percentage kernel of `Schley', and nut size of both cultivars were increased by irrigation or irrigation and fertigation. The 100 lb/acre N-all-fertigated treatment resulted in less soil pH reduction and less loss of K, Ca, and Mg from soil underneath the tree canopy than broadcast treatments. No evidence of excessive soil pH reduction in the wetted zone of fertigated trees was noticed. Calcium and Mg were higher within than outside the wetted zone.
Nitrogen at rates of 112 or 224 kg·ha-1 was applied to nonirrigated and drip irrigated mature pecan trees for 9 years. Some irrigated trees received 224 kg·ha-1 N either all broadcast or ½ through the drip irrigation. Other drip irrigated trees received only 112 kg·ha-1 all through the drip irrigation system. Fertigation was in 4 equal monthly doses beginning April 1. Irrigation increased yield for 2 years for Schley and 3 years for Stuart. Nut size was increased by irrigation in 6 years for Schley and 8 years for Stuart. Applying ½ N through the irrigation system caused no detrimental effect on yield or nut quality. The lower rate of N all applied through the drip irrigation system gave yield and nut quality as good as the higher rate either all broadcast or ½ broadcast and ½ fertigated.