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CALIFORNIA FRUITS I HOW TO GROW THEM 



is greenish black or bronze colored, copper colored on the under side. 

 If any tree receives any damage to the bark, either by sunburn or other 

 causes, the borer is sure to find it, and it works itself into the tree, its 

 castings being the only guide to its presence. The best remedy is pre- 

 vention by protection from sunburn, as described in Chapter XI. 

 Whenever a borer is removed, the debris and dead wood should be 

 entirely cleaned out and the smooth surface left, taking care to pre- 

 serve the bark as much as possible. Then the wound should be smeared 

 over with grafting wax, and a rag tied about it. In this manner young 

 trees have been saved, but if seriously attacked, it is better to put in 

 a sound tree and protect it. 



Sun-Scald Borer. Another borer which delights in sunburned 

 trees is a minute beetle, making a burrow hardly larger than a pinhole. 

 It is known as the sun-scald beetle (Xyloborus xylographus). The 

 remedy, as in the former case, is to prevent injury to the bark, for this 

 precedes the attack of the beetle. 



Peach twig showing winter burrow, natural size. 



The Olive Twig-Borer. A reddish brown beetle boring into 

 twigs of olive and other orchard trees, and grape canes, at the axils 

 of the leaves. It is Polycaon confertus, and it breeds in decaying logs 

 and stumps and old grape-vines, apparently visiting the fruit trees 

 merely to gratify its appetite. Its work is not fatal to the tree, but 

 unless proper pruning and attention be afterwards given, it may spoil 

 the shape of the young tree. Remove the affected branches below the 

 burrows of the beetle, or if it would be difficult to replace a branch, 

 see that the beetle is destroyed and the entrance to the hole stopped up 

 this to prevent decay and a weak branch following. Spraying with 

 ill-smelling solutions may prevent their attack, but the insect has not 

 been sufficiently abundant to invite serious effort thus far. 



Peach Crown-Borer. A grub boring into peach trees just below 

 the ground surface, its presence being shown by copious gumming. 

 The insect, which has become quite troublesome in Santa Clara County, 

 resembles the Eastern crown-borer of the peach, but is a distinct species 

 (Sanninoidea opalescens). The best methods of suppressing this insect 



