Care of Bearing Trees
Fertilizing: Fertilization is one of the most important practices for bearing trees. If the trees are to produce a good crop, terminal growth should be 6 inches each year. In the absence of a leaf tissue analysis or soil test, broadcast 4 pounds of a complete fertilizer such as 10-10-10 for each inch of trunk diameter (measured 4½ feet above soil level). This fertilizer should be applied in mid- to late February.
Zinc nutrition is especially important in pecan production. Zinc deficiency is called rosette. The most common and noticeable symptoms of rosette are bronzing and mottling of leaves; early defoliation; dead twigs in tops of trees; abnormally small nuts; small yellowish, chlorotic leaves; and short, thin twigs growing on older scaffold branches with rosettes of small yellowish-green leaves at the tips.
Zinc needs are best determined by a laboratory analysis of leaf samples taken in late July or early August. Kits and instructions for taking leaf samples are available from any Clemson Extension office. The leaf tissue analysis report will tell you how much zinc to apply. In the absence of a tissue analysis, apply 1 pound of zinc sulfate to young trees and 3 to 5 pounds for large trees each year. A soil pH of 6.0 to 6.5 assures the availa-bility of essential nutrients. If the pH is too low or too high, uptake and use of nutrients is impaired. Apply lime as suggested in the soil test report to correct low pH.
