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TREES AS GOOD CITIZENS 



BORING INSECTS 

 Sugar Maple Borer 



Habits This is the worst insect 



and enemy of the Sugar Maple. 



Damage. It differs from other borers in 

 that its attack is made against 

 trees which have not been weakened. As 

 a result of its work large limbs and even 

 entire trees may be killed. The parent 

 insect appears between June and August, 

 emerging from oval holes in the bark. At 

 this stage it is a thick, black beetle, about 

 one inch long, with short horns, and 

 marked with brilliant yellow. Egg-laying 

 occurs during July or August, causing 

 discoloration of the bark upon the trunk 

 and larger branches. The larvae begin 

 boring soon after hatching, and their 

 work causes a flow of sap and throws out 

 a substance which often forms a small 

 mass on the surface at the point of 

 entrance. The first winter is spent on the 

 sapwood and in the following spring the 

 borer tunnels between bark and sapwood 

 or into the outer sapwood. The burrows 

 during the second summer are half an inch 

 or more in width and almost as deep, 

 and they form serious wounds. If these 

 tunnels girdle a tree or limb they cause 

 death. 



The presence of the borer may be 

 detected by various signs, including dead 

 limbs, dead areas of bark, ridges or eleva 

 tions just under the bark, naked scars on 

 limbs or trunk, especially near the base of 

 a large limb, oval holes about half an inch 

 wide and a substance resembling sawdust 

 at the base of the tree or in bark crevices. 

 Sometimes the leaves on a limb will sud 

 denly dry up and die, and a flow of sap 

 and "sawdust" will be found somewhere 

 on the limb. 



Remedies. Careful examination of 

 trees for signs of the presence 

 of borers should be made every spring and 

 fall. If discoloration of the bark and 

 exuding sap indicate that eggs have been 

 laid, or if sawdust or excrement have 

 exuded, prompt action for control should 

 follow. The first step is to cut away the 

 bark and follow the burrow till the grub is 

 located and destroyed. The cutting must 

 be done with great care, with clean sur 

 faces, and the wounds covered with creo 

 sote-tar mixture or two coats of good 

 white lead paint. Sometimes the grub 

 may be reached, and killed by probing 

 with a flexible wire to the end of the 

 burrow. Carbon disulphid injected into 

 the holes will kill the borers if all openings 

 are promptly plugged with wax, soap, 

 clay or putty to shut out air, but when 

 this method is used it is not possible to 

 know that the borer has been killed. 



Spraying the tree in late summer with 

 poisoned kerosene emulsion or miscible 

 oil is effective in killing borers which have 

 just penetrated the bark. The spray 

 should be confined to the trunk and the 

 larger branches and care must be taken 

 that none of it reaches the foliage, as the 

 leaves are seriously injured by these 

 solutions. 



Trees which are badly infested, or dying 

 trees or branches, should be cut down and 

 burned. This should be done during the 

 winter and spring, to prevent any of the 

 adult beetles from emerging and causing 

 damage to other trees. 



Leopard Moth 



(See description and remedies under Elm) 

 Carpenter Worm 



Habits While seldom causing the 



and death of a tree, this worm is 



Damage, responsible for serious deform 

 ities which result in unsightly 

 appearance. Its eggs are laid near 

 wounds or scars and it is through such 



Prevention The most effectual treat- 

 and ment of this insect is to take 



Remedies, steps to prevent a tree from 

 becoming infested. Since 

 wounds and scars invite the laying of eggs, 

 it is important to see that no wounds 



