38 MANUAL OF TROPICAL AND SUBTROPICAL FRUITS 



each irrigation. In southern Florida other methods are made 

 necessary by the fact that water cannot be run in furrows over 

 the sandy soil. Revolving sprinklers, placed at the proper 

 distance so that all the ground will be covered by their spray, 

 are sometimes employed. Where economy of water is a factor, 

 these are less desirable than the basin system. Taken in all, 

 it seems that the best method of irrigating is to form around 

 the tree a basin as wide as the spread of the branches (or wider 

 during the first two years), to fill it with weeds, straw, manure, 

 seaweed, or other loose mulch, and then to apply water at 

 least once in two weeks when the rainfall is not sufficient to 

 maintain the tree in good growing condition. 



Pruning. 



The amount of pruning required by the avocado depends 

 largely on the variety. Some make short stocky growths and 

 form shapely trees without the assistance of the pruning- 

 shears, while others take long straggling shapes and do not 

 branch sufficiently to form a good crown. These latter must be 

 cut back heavily. Trapp, and other varieties of the West 

 Indian race in general, usually make low stocky trees, branch- 

 ing abundantly and forming plenty of fruiting wood. With 

 such forms, pruning is reduced to the minimum, consisting 

 principally in removing fruit-spurs which die back after the 

 crop has been harvested, and in the occasional cutting back 

 of a branch to produce a crown of symmetrical form and good 

 proportions. Beyond this very little pruning is done in 

 Florida orchards. 



With the Guatemalan race, more training is often necessary 

 to produce a tree of ideal proportions, since some varieties tend 

 to make long unbranched growths. In others the lateral 

 branches are very weak and scarcely able to bear their own 

 weight if allowed to develop unhindered. With these, care- 

 ful attention should be given during the first few years to pro- 



