INSECTS AFFECTING PARK AND WOODLAND TREES 547 



one on each wrinkle, tipped with whitish or pink and extending along the 

 abdominal segments. The two posterior thoracic segments are each orna- 

 mented with a pair of straight tuberculated horns, a line of granulations 

 connecting them. Seven oblique stripes of whitish granulations occur on 

 each side, each reaching from one segment across the following and onto 

 the third, the last stripe extending to the caudal horn. The parent insect 

 is a magnificent sphinx moth with a wing expanse of about 5 inches. The 

 fore wings are broad with a large, distinct, round discal spot, light brown 

 and variously marked with dark brown. The abdomen is marked with a 

 narrow, black, dorsal line, a crenulate black, subdorsal line and a somewhat 

 broken, black, lateral line. 



Spring canker worm 



Paleacrita vernata Peck 



Dark striped measuring worms about an inch long, defoliate apple and elm trees in 

 early spring. 



This species is a well known apple pest in New England and inflicts 

 considerable loss in certain portions of New York State. Its original food 

 plant is the elm, and occasionally it is somewhat injurious to this, though 

 most of the injury in later years has been in apple orchards. The fall 

 canker worm, Anisopteryx pometaria Harr., is a closely allied 

 form possessing similar habits except that the adult is more likely to 

 emerge and deposit its eggs in the fall, whereas the spring canker worm 

 does not usually appear till very early spring. The eggs of both hatch 

 about the time the leaves begin to appear, and where the pest is at all 

 abundant defoliation quickly follows. The caterpillars complete their 

 growth, forsake the tree and transform to pupae in the soil. This makes 

 it possible to take advantage of the wingless condition of the female and 

 injury can be prevented by employing a sticky band in early spring or fall 

 as the case may be, or by thorough spraying with an arsenical poison. 



