Elm leaf beetles spend the winter in sheltered dry places. In 
the Northeastern States most of them hibernate in house attics, 
barns, and sheds. During periods of warm weather in the winter 
many of these become active and cause considerable annoyance by 
crawling into living quarters or onto windows. Spring emergence 
begins about the time the buds of elm begin to swell, and the 
adults fly to nearby elms and feed by chewing holes in the un- 
folding leaves. Egg laying begins late in May or early June, each 
female laying from 400 to 800 eggs (725). Hatching begins in 
about one week and the larvae feed for 2 or 3 weeks on the under- 
surfaces of the leaves. Only the veins and upper surfaces are left, 
and the leaves soon dry out and turn brown. Full-grown larvae 
crawl down the tree and pupate in bark crevices or at the base of 
the tree. In the eastern United States there may be one or two 
complete and a partial third generations. Usually the first gener- 
ation is the most injurious. Beetles maturing in the summer begin 
entering hibernation quarters on or near the tree on which they 
fed as early as August. : 
Shade tree elms are often heavily defoliated, whereas those 
growing in the forest are usually not seriously infested. The 
native parasite, Tetrastichus brevistigma Gahan occasionally ex- 
erts a considerable degree of control in the Northeastern States 
(62). During damp weather the fungus, Sporotrichum globuli- 
ferum, is also occasionally effective in control. Some degree of 
direct control of beetles hibernating in attics can be obtained 
locally by trapping them as they are leaving their hibernation 
quarters in the spring. Most of the openings that admit light 
should be covered with black paper. The remaining openings 
should be covered with tightly stretched cellophane attached to 
wooden frames. The inner surface of the cellophane should be 
covered with a sticky substance such as Tanglefoot. 
Pyrrhalta cavicollis (LeC.) occurs in southern Canada and in 
the Eastern States southward through the Alleghenies and Appa- 
lachians to North Carolina and westward to the Rocky Mountains. 
Its preferred host is pin cherry but it also feeds on plum, other 
cherries, and peach in heavily infested areas. The adult is red, 
shining, coarsely punctured, and about 5 mm. long. Larvae are 
dark brown, with black and yellow spots, and are about 6 mm. 
long. 
The winter is spent in the adult stage. In the spring, eggs are 
deposited in the soil at the base of the tree, or on the trunk near 
the base. The larvae climb the tree and feed on the foliage. Full- 
grown larva return to the ground and pupate in the leaf mold or 
soil. There is one generation per year. P. decora decora Say and 
P. tuberculata (Say) feed on willows. 
The elm calligrapha, Calligrapha scalaris (LeC.), has been re- 
ported from eastern Canada and from several widely distributed 
points in eastern United States. Its preferred and probably only 
host is elm. Adults are elongate-oval, creamy-white beetles from 
8 to 10 mm. long. The head and thorax are dark, metallic green. 
Each elytron bears from 10 to 14 metallic green spots, a dark 
green, boot-shaped spot at the base, and a dark, metallic green, 
irregular stripe along the inner edge. Full-grown larvae are 
hump-shaped and have yellow heads. The abdomen is light yellow 
or cream-colored with a black line down the middle of the dorsum. 
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