TREE INSECTS AND THEIR CONTROL 219 



of yellow hairs, long, soft and drooping, 

 with five tufts of stiff black hairs on its 

 back. The moths emerge from the chrys- 

 alis in the spring and lay their eggs. 

 From these are developed the caterpillars, 

 which feed on the leaves and which when 

 at rest, curl up on the under side of leaves. 



SAP-SUCKING INSECTS 

 San Jose Scale 



(See description and remedies under Ash) 



BORING INSECTS 

 Aspen Borer 



Habits This borer does considerable 



and damage to Poplars, and is 



Damage, especially prevalent in the 

 middle and western states. 

 The parent insect is a gray beetle, cylin- 

 der shaped, having brown spots. This 

 beetle's eggs are laid in a scar in the bark, 

 in May, June and July. On hatching, the 

 grub begins its mining, and spends its 

 first year tunneling just beneath the bark, 

 following this with two years of mining 

 deep into the wood. The boring grub is 

 cylindrical, yellowish, and has a number 

 of fine, short, hard points on a plate 

 immediately behind its head. The sign 

 of this borer's presence is the appearance, 

 in June or July, of irregular scars on the 

 trunk of a tree, especially near crotches, 

 from which there exudes sap carrying 

 fibrous dust from the boring. Later there 

 is an enlargement of the holes, with 

 increased mass of discharge. 



Remedies. Spraying infested trunks 

 in late summer with poisoned 

 kerosene emulsion or miscible-oil solution 

 is effectual in destroying the young grubs 

 in the outer bark. Another helpful meas- 

 ure is painting the eggs with creosote 

 or carbolineum. When the young borers 

 begin to tunnel into the wood in the fall, 

 they may be dug out and killed; careful 

 attention should be given to dressing the 

 wounds caused by this treatment. Trees 

 badly infested should be cut and burned. 



Bronze Birch Borer 



(See description and control under Birch) 



Mottled Willow and Poplar Borer 



Habits Of the enemies of Poplars 



and and Willows this is the most 



Damage, dangerous. The parent insect 

 is a broad and stocky snout- 

 beetle of dark brown coloring mottled 

 with gray, and with pinkish tint at the 

 rear of the wing covers. In length it is 

 about Y% inch. After emerging from the 

 chrysalis stage in June or July the beetles 

 feed on the young bark and after a fort- 

 night the female deposits eggs in cavities 



Remedies. The surest way to destroy 

 this enemy is by cutting and 

 burning infested limbs or badly infested 

 trees. This must be done in early sum- 

 mer, before the insects emerge from the 

 interior, in order to make sure that all of 

 them are destroyed. This season is a time 

 of great activity on the part of the grubs 

 and the exuding sap and "sawdust" make 

 it easy to detect their presence. A 

 thorough coating of the bark with lead 



