76 STATE HORTICULTURAL SOCIETY. 



BOREES THAT THE HORTICULTURIST MUST FIGHT. 



BY PROF. G. C. DAVIS, MICHIGAN AGRICULTUEAL COLLEGE. 



APPLE TREE BOREES. 



What is commonly known as the flat-headed apple tree borer is one of the 

 commonest that we have. It is so named from the flat appearance of the head 

 of the grub and can be told the flattened burrow which it makes. The 



grub may further be known by the anterior por- 

 tion just back of the small head being enormously 

 enlarged and rounded on the sides. But one year 

 is required for the development of these borers 

 and hence they grow rapidly and bore with equal 

 energy to satisfy the appetite. They pupate in 

 the spring in their burrows and come out as a 



FLAT hITded apple teee beetle in early June. 

 BoBEB (chrysobothris femo- The beetles are great lovers of sunshine, and 

 a, arva,6, eet e. .^^^ ^^ &een quietly basking on the sunny side 

 of a fence, stump, or tree, or perhaps running very rapidly around as if 

 in search of something, instantly taking wing if one tries to catch them 

 with his hand. 



Through June and July, the eggs are laid in crevices over the bark, 

 and the young grub, like all others of this family of borers, has to gnaw 

 its way through to get under the bark. 



Besides working on the apple, this species is known to work on the 

 cherry, pear, plum, peach, and most of our shade trees and shrubs. It is 

 even more common in the forests than in our orchards, so that the species 

 is not likely to become extinct for want of a food plant. As a general 

 rule, in depositing their eggs, the beetles will select a tree that is not 

 really thrifty or rugged in its growth. Small trees that have been 

 recently transplanted are also sought for the same reason, and special 

 attention should be given such trees to prevent the borer from taking 

 undue advantage of them for a few years until they become as thrifty 

 and rugged as the rest. 



Dead, partly decayed, or badly injured branches should never be per- 

 mitted to remain in an orchard, neither on the tree nor off, as they are 

 ideal breeding places for the flat-headed borers. Such branches as these 

 in an orchard not only breed the borers very rapidly, but attract others 

 that are traveling. When the dead or sickly trees have been killed off, 

 the beetles will attack the thrifty trees and they in turn will succumb 

 to the beetle's work. Brush piles left in an orchard or vicinity are 

 equally good harbingers of all kinds of borers as well as other vermin. 

 I feel very certain that I am right when I make the assertion that no 

 orchardist need worry over the flat-headed borer injuring his trees to any 

 extent if he will keep his orchard in a healthy condition and keep all dead 

 and dying limbs cut out and burned. So long as an orchard is kept in this 

 condition there is nothing to attract the beetles and they will leave the 

 orchard entirely alone and search for orchards more to their liking. 



