PRUNING CITRUS TREES. 377 



with branches already developed, they may be carefully 

 drawn down out of the tree, below the lowest branches 

 and bent out to one side, there to grow into large, strong 

 branches, thus bringing the head of the tree closer to the 

 ground. 



Pruning for Insect Treatment. If citrus trees are 

 to be sprayed, it is often essential to thin out some of the 

 interior branches, that the spray may be thoroughly and 

 easily applied. The pruning must not be too vigorous, 

 however, and no more of the center branches should be ,' 

 sacrificed than is absolutely necessary. Heavy pruning 

 is too frequently followed by a vigorous growth of water- 

 sprouts, and unless these are 1 promptly checked, the in- 

 terior of the head will become as dense as before. Upon 

 no condition should so many of the branches be removed 

 as to allow the rays of the sun to penetrate and strike 

 the branches. It is essential that the trunk and larger 

 branches be protected by a mass of leafy twigs. Dead, 

 dry branches, the result of the strong rays of the sun, clear- 

 ly show the necessity of this. Citrus trees, as a whole, are 

 not like deciduous trees. The latter should be pruned so 

 as to admit the strong sunlight to all parts of the head; 

 but not so with citrus trees. A head, the shape of a 

 hollow cone, may be developed, but the outer band or 

 zone of foliage must be sufficiently dense to exclude the 

 strong, and to the branches, injurious rays of the sun. 



Pruning in Relation to Die-back. In Florida it has 

 frequently been observed that die-back follows the freez- 

 ing back of the tops of citrus trees. The roots, as a rule, 

 remain uninjured, and large amounts of materials in 

 solution are collected. The enzyme producing die-back 

 enters the trunk in large quantities, and the disease be- 

 comes manifest. Exactly the same condition may result 



