The locust leaf miner, Odontota (=Xenochalepus) dorsalis 
(Thunb.), occurs in southern Canada and throughout most of 
eastern United States. Its favored host is black locust, but several 
other tree species such as apple, birch, beech, wild cherry, elm, 
oak, and hawthorn are also attacked occasionally. The adult is an 
elongate, flattish beetle about 5 to 6 mm. long. The head is black 
and the thorax and most of the wing covers are bright orange. 
The inner edge of each elytron is black, with the blackened area 
widening posteriorally. The elytra are also deeply pitted, and each 
elytron bears three longitudinal ridges. A full-grown larva is 
yellowish-white, somewhat flattened, and a little longer than the 
adult. 
The winter is spent in the adult stage in bark crevices or under 
debris on the ground. Overwintering adults emerge in the spring, 
about the time the leaves begin to unfold, and feed for a short 
time on the leaves, skeletonizing the lower surfaces and eating 
holes in them. Eggs are deposited on the lower surfaces of leaves 
in groups of three to five eggs each. They overlap like shingles on 
a roof, are glued together, and are covered with excrement. All 
the larvae from a given group of eggs bore into a leaf and feed 
in a common mine. Later, they separate, and each larva feeds in 
its own mine. Before reaching maturity, a single larva may mine 
several leaves. Pupation occurs in the mine, and there is one 
generation per year. 
Outbreaks of the locust leaf miner occur practically every year 
somewhere within its range and black locust trees on tens of 
thousands of acres are often defoliated. The defoliated trees are 
seldom killed, however, unless the damage is incurred during poor 
growing seasons. At such times trees may be killed in large 
numbers (381). The eulophid parasite, Clostocerus tricinctus Ash- 
mead, is reported to have destroyed over 50 percent of the pupae 
in West Virginia infestations (747). Direct control is seldom at- 
tempted in the forest, but is sometimes desirable in parks and 
other recreational areas. 
The imported willow leaf beetle, Plagiodera versicolora 
(Laich.) (fig. 42), an introduced species, was first reported in 
this country from Staten Island, New York in 1915 (366). It is 
now widely distributed in the Eastern States and southern Canada 
(it has also been reported from Alaska) where it feeds on several 
varieties of willow and poplar. The adult is moderately stout, 
oval, and about 3.5 to 4.5 mm. long. It is metallic blue or greenish- 
blue in color, and sometimes tinged with red or bronze. Full- 
grown larvae are almost jet black and about 5 mm. long. Rows of 
protuberances run both transversely and longitudinally across and 
along the body. 
The winter is spent in the adult stage under the bark, or in 
debris or tufts of grass around or near the base of trees. The 
beetles emerge in April or May and feed for a short period by 
skeltonizing the leaves or by cutting holes through them. Then 
the female lays irregular masses of eggs on the leaves. Hatching 
occurs in about a week. The larvae are gregarious and feed in 
groups or in rows on the leaf surfaces which they skeletonize. 
Three and a partial fourth generations per year have been re- 
corded in Massachusetts. Additional generations probably occur 
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