PRUNING CITRUS TREES. 387 



quickly performed, the number of limbs to be cut being 

 greatly reduced, and all being within reach from the 

 ground. 



An explanation of the details of this system should 

 properly come under two heads: "Pruning of young 

 trees/ 7 and "Altering old trees." As most of the lemon 

 trees in California are three years old or over, this paper 

 will be confined to a discussion of the method of altering 

 old trees to conform to the "open-center" style. 



It is assumed that the trees to be altered are branched 

 fairly near the ground. If they have been up high no sys- 

 tem of pruning will bring the fruit within a reach from the 

 ground, but to cut out the tops will save sap and make the 

 lower limbs, such as they are, more fruitful. 



Assuming, then, that the grower has trained his trees 

 near the ground, and has not caused the branches to grow 

 up for elephants to walk under, the method of procedure 

 is as follows: Draw an imaginary line around the out- 

 side of the tree, as high up as a man can reach standing 

 on a picking-box. All the limbs that terminate above this 

 line should be cut out. Cut them off at their juncture 

 with the limbs that terminate below the imaginary line. 

 When this is done the top of the tree, looking down into 

 it, will look like the inside of an inverted cone, and the 

 tree may be called open-centered. 



If the trees are small, cut out all limbs that extend 

 up from the center of the tree at an angle greater than 

 forty-five degrees from the horizontal. The tree in appear- 

 ance will then be proportionately the same as the older 

 tree above described, and can be trained gradually to the 

 same limit of height. 



The) after-treatment of an open-centered tree, what- 

 ever its size, resolves itself into two distinct operations: 



