Citrus Tree Spacing Effects On Soil Water Use, Root Density, And Fruit Yield

ABSTRACT Soil water content, root density, and fruit yield measurements were made on 'Hamlin' orange trees on Milam rootstock at two tree spacings-6 x 4.5 m (370 trees/ ha) and 4.5 x 2.5 m (889 trees/ ha). Soil water use per unit land area for the seven- and eight-year-old trees was not significantly affected by tree spacing. Water use was greatest underneath the canopy dripline and generally decreased with increasing soil depth to 1.65 m. Root densities of the seven-year-old trees were greater at the 4.5 X 2.5 m spacing and generally decreased with depth. Fruit yields per ha were greater for the 4.5 x 2.5 m spacing in the early years, were comparable for both spacings during the seventh and eighth years, and favored the 6 x 4.5 spacing in the 9th year..