2IO 



TREES AS GOOD CITIZENS 



Twig Girdler 



(See description and remedies under Elm) 



GALL INSECTS 

 Gall Aphis 



Swellings which resemble Remedy. To destroy these insects a 



Habits 



and tumors and cause deformity 



Damage, of the twigs and leaves are 

 produced by this insect when 

 spring growth starts. The actual damage 

 is slight, but the appearance of a tree may 

 be badly marred by the galls. 



spring spraying of kerosene 

 emulsion should be applied at the time the 

 buds are opening. This kills the insects 

 and prevents the creation of the deform- 

 ing gall growths. 



HONEY LOCUST 

 White-marked Tussock Moth. Twig Girdler. 



(See description*and remedies under Elm) 



HORSE CHESTNUT 

 White-marked Tussock Moth. 



Oyster-shell Scale 



(See description and remedies under Elm) 



Leopard Moth. 



BORING INSECTS 



Twig Girdler 



(See description and remedies under Elm) 



Linden Borer 



Habits This beetle confines its 



and attacks to the Linden, in 



Damage, which respect it is different 

 from other insect enemies of 

 this tree, listed above. The attacks often 

 cause serious injury. The borer eats the 

 green bark of growing shoots, the leaf 

 stems and the larger veins on the under- 

 side of the leaves. The attack becomes 

 noticeable toward the close of summer. 

 Damage by boring is done by the grub, 

 which eats its way under the bark and 

 deep into the wood of the trunk, near the 

 ground, and into exposed roots and lower 

 limbs. The insect appears in May and 

 begins its attack. Eggs are laid soon 

 afterwards in incisions in the bark. After 

 passing through transformations from 

 grub to beetle, the insect leaves the tree 

 through holes in the bark. The time of 

 departure is throughout the summer. In 

 appearance the beetles are long-horned, 

 with six black spots on the back. 



Remedies. The surest method of 

 destroying this borer is to 

 dig it out bodily, whenever this is possible. 

 This is especially desirable in the case of 

 a valuable tree, to make sure of the elim- 

 ination of the enemy. Another method 

 employed with good results is to kill the 

 borer bodily, by probing with a wire into 

 the burrow. Injection of carbon disul- 

 phid is effectual when thoroughly done. 

 Spraying with poisoned miscible oil solu- 

 tion in the late summer helps in the 

 destruction of the borers. When a tree is 

 heavily infested and badly damaged it is 

 best to cut the tree down and burn it, as 

 the damage can not be overcome and the 

 tree is a menace to its neighbors if it is 

 allowed to stand. 



