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UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 



burning frequently resulted on the south side of defoliated young 

 lemon trees in particular and the whitewashing of the trunks of such 

 trees soon after a freeze is important. 



Aside from whitewashing, there seems to be but one fixed rule, 



and that is to let the trees alone until the 

 new growth is well under way, and the 

 demarcation between dead and living wood 

 has become plainly apparent. 



The method of renewal of young trees 

 depends entirely on the degree of injury. 

 If the trees have lost only a portion of 

 their heads, a new head may be shaped 

 after the growth is well under way. With 

 trees that lost their entire crowns but re- 

 tained sound trunks, as happened in many 

 cases especially where they had been pro- 

 tected by a wrap during the freeze, it 

 proved to be thoroughly practical to train 

 three or four sprouts, properly located 

 and spaced near the top of the trunk, to 

 form the new head. 



If the trunk is killed too far down to 

 produce a good-shaped head, but is still 

 living above the bud, the best method of 

 renewal is to select a strong sprout that 

 springs out above the bud and train it 

 into a new tree, retaining the old trunk 

 as a supporting stake until the sprout 

 becomes strong enough to need no support. 

 Remove all other sprouts and throw the 

 full strength of the tree into this one 

 sprout. Many young sprouts that did not 

 even start growing until the middle or 

 latter part of March, trained in this man- 

 ner and headed before the August growth, 

 in seven or eight months made splendid 

 vonng trees, better than new trees planted 



m the spring. Whatever system of renewing young trees is followed, 

 it is important to start below all large areas of dead wood. There is 

 too much at stake to grow a new tree for several years on a rotten 

 foundation. If the main crotch has been badly frozen and the dead 

 bark and wood extends downward from this injury, sacrifice the top 

 and start the new head from healthy tissue (fig. 15). 



Fig. 15. The develop- 

 ment of a new tree from a 

 sprout springing from base 

 of trunk above the bud, the 

 old trunk being retained for 

 a time as a stake for the 

 new tree. Photo by Tylor, 

 September 6, 1913. 



