INSECTS AFFECTING PARK AND WOODLAND TREES I05 



DESTRITCTIVE 1.KAK FKEDEnS 



Certain species of leaf feeders have been exceedinj^^ly destructive to 

 shade trees in New York State in recent years, and in making selections for 

 this group it is probable that some will be omitted, which, in the course of 

 a few years will attract notice on account of their depredations. 



Key to destructive leaf feeders 



Blue-headed caterpillars with a line of silvery diamond-shaped spots down the middle of 



the back, rest in masses on the sides of branches and trunks and defoliate maple and 



other trees in midsummer. . Forest tent caterpillar, M a 1 a c o s o m a d i s s t r i a, p. 106 



Brownish caterpillars with blue and reddish warts, occur in masses on the sides of 



branches and trunks of many trees in early summer 



Gipsy moth, Porthetria dispar, p. 116 

 Curious baglike shelters containing cateri)illars, occur in early summer on various trees 

 and shrubs in the vicinity of New York city 



Bag worm, T h y r i d o p t e r y .\ e p h e m e r a e f o r m i s, p. 1 23 

 Light green, white marked caterpillars about 2 inches long sometimes occur in immense 



numbers on soft maples in early summer X y 1 i n a a n t e n n a t a, p. 129 



Red-headed, yellow and black tufted caterpillars defoliate in early summer horse-chestnut, 

 linden, maple and other trees 



AVhite marked tussock moth, Hemerocampa leucostigma, p. 132 

 Conspicuous web tents in July and August, inclosing foliage at the tips of branches, which 

 is soon skeletonized and turns brown 



Fall webworm, Hyphantria textor, p. 142 

 Irregular, circular holes in elm leaves, particularly of European species, followed by 

 skeletonizing of the under surface of the foliage by grubs 



Elm leaf beetle, Galerucella luteola, p. 146 

 Cylindric, coiled, yellowish white worms with a black line down the middle of the back, 

 occur in midsummer on willow, elm, poplars and other trees 



Elm sawfly, C i m b e .x a m e r i c a n a, p. 155 

 Large, black, red-marked, spiny caterpillars 2 inches long, occur in June and August in 

 clusters and defoliate terminal branches of elm, willow, poplar and other trees 



Spiny elm caterpillar, Euvanessa antiopa, p. 158 

 Circular, somewhat irregular mines occur in considerable numbers in the leaves of 



European and American elms Elm leaf miner, Kaliosyphinga ulmi, p. 162 



Small web tents on tips of trees in midwinter 



Brown tail moth, Euproctis chrysorrhoea, p. 163 



