32 CALIFORNIA AGRICULTURAL EXTENsioN Service [Circ. 42 surprising how quickly an individual can learn to closely estimate the number of peaches on a tree with a little practice. A thinning schedule adapted from Weldon is shown in table 2. Any desired vield ean be computed from the fieures given. TABLE 2 THINNING SCHEDULE OF PEACHES Number of peaches to be left on each tree to produce the tonnages indicated, of the 24-inch or of the 2%4-inch size Tons per acre desired Trees planted 20 feet . by 20 feet (108 per acre) > 14-inch size 23/.inch size Trees planted 24 feet by 24 feet (75 per acre) 23-inch size 3lé-inch size 70 54 101 7 350 270 505 385 700 | 540 | 1010 | 770 1050 810 1515 1155 Peaches are thinned by hand. All misshapen, blemished, or other- wise inferior fruits are removed, leaving one specimen to a eluster, and spacing the remainder to the desired distance. In connection with thinning, judicious dormant pruning to remove excess fruiting wood is helpful. Under some conditions, such as low priees or shortage of labor, thinning may be done by means of long poles. Bracing. *>—When the crop is heavy, propping or bracing is neces- sary to prevent the breakage of limbs (fig. 7). Young trees may be supported by passing rope around the outer limbs. After the trees have attained sufficient height, a permanent system of wiring may be installed. There are various systems and kinds of equipment used ranging in cost from 25 to 35 cents per tree. Removal of Trees—In the case of unprofitable orchards or of orchards too closely planted it is sometimes necessary to remove all or some of the trees. This may be accomplished best by pulling them when the ground is wet, or by blasting when the ground is dry. One method of removal by pulling is by means of a team or tractor and a tackle with a chain around the trunk near the ground. Another method is by means of a portable derrick (fig. 8), which is set in place over the stump to be removed. Trees to be removed may previously be cut back to stumps and these left to die and the roots to partially 15 Barnard, L. C. Central wire bracing for fruit trees, California Agr. Exp. Sta. Cir. 244:1-10. 1922,