across the thorax and wing covers, the third band on the wings being W-shaped. 
The legs and antennae are moderately long and yellow. Full-grown larvae are robust 
and about 25 mm long. 
Adults are present in late summer or early fall, but are most abundant during 
September. They are commonly seen feeding on the pollen of goldenrod blossoms 
during morning hours. Later in the day, sometimes well after sunset, they are 
usually seen running up and down the trunks of black locust trees in search of 
oviposition sites. Eggs are usually deposited in rough bark crevices and around 
wounds on the trunks of living trees. Newly hatched larvae bore into the inner bark 
and construct small hibernation cells in which they spend the winter. Activity 1s 
resumed in the spring when the leaf buds begin to swell. At this time, oozing sap 
may be seen around larval entry holes in the trunk. The larvae soon bore into the 
wood where they continue to feed until mature, around mid-July. During this period 
they construct extensive tunnels throughout the heartwood (fig. 125A). As the larva 
grows, it enlarges its tunnel to the exterior, through which it pushes its granular 
frass to the outside and through which the adult eventually emerges. There is one 
generation per year (464, 1352). 
The locust borer has destroyed thousands of hectares of natural regeneration and 
plantations of black locust. Enormous numbers of older trees, especially slow- 
growing overtopped trees, have also been badly damaged or killed. However, 
vigorous dominant trees over 10 years old have seldom been killed. Infested trees 
are physically weakened by the larval tunnels, the smaller ones often being re- 
stricted to shrub form by repeated attacks (fig. 125B). Trees growing on poor sites 
are especially susceptible to attack and suffer serious damage during periods of 
prolonged drought. 
A number of practices have been suggested for the prevention or reduction of 
damage by the locust borer. These include planting superior varieties of black 
locust, the use of mixed species in planting, the removal of old stag-headed brood 
trees, selection of good sites for planting, thinning and mulching of stands, and 
protection of young trees from fire or livestock grazing (5/5, 830, 1351). 
The painted hickory borer, M. caryae (Gahan), is widely distributed in the 
Eastern United States. Freshly cut hickory logs are normally preferred for breeding, 
but dead trees of several other hardwoods such as black locust, honeylocust, oak, 
hackberry, mulberry, walnut, butternut, and ash also are attacked occasionally. 
Hickory wood cut during the winter may be completely riddled by midsummer. The 
adult closely resembles the adult of the locust borer, but is slightly shorter on the 
average, ranging from 10 to 20 mm long. The elytra also are more tapering, the 
prosternum is wider than long, and the antennae of the male are longer than the 
body. 
Adults emerge in early spring and deposit their eggs beneath bark scales on logs 
cut the previous winter. The larvae feed for several weeks under the bark and then 
bore into the sapwood and later the heartwood. Pupation occurs in the fall at the end 
of the larval mine behind a wad of fibrous frass. The adult, like the adult of the 
locust borer, emerges through the larval gallery and entrance hole. Winter is spent 
in the pupal stage and there is one generation per year. 
Megacyllene antennatus (White), commonly known as the mesquite borer, 
breeds in mesquite and acacia in Texas and other Southwestern States. The adult is 
robust, brownish black, and from 12 to 30 mm long. It is marked with fine white or 
gray hairs and a dark spot in the center of the thorax. Eggs are deposited in crevices 
of the bark of recently cut wood. The larvae feed first beneath the bark and then in 
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