Determine from Table 1 the cross-sectional trunk in square feet for each tree. If the total is greater than 30, too many trees exist for optimum pecan production. A total of 30 square feet of trunk cross section is the maximum recommended for one acre. Measure diameter four feet above ground. With experience it will not be necessary to utilize this time consuming measuring procedure.
Most individuals are soon capable of approximating stocking rates via visual observation.
Since native trees are randomly spaced, tree thinning cannot be performed by systematically removing specific rows of trees as found in formal plantings. Instead, tree removal in native groves is commonly considered on an individual basis. Symptoms of tree crowding are small leaves of light green color and early shedding of the leaves in the fall. Short shoot growth, shedding of the lower branches, and irregular, low nut production also occur. The first step in developing a native grove is to remove all underbrush and all timber that is not pecan.