and turn black. Eggs are deposited in pits chewed in the bark 
below the ground line at the base of the tree. Young saplings and 
nursery stock are subject to attack, but larger trees are usually 
selected. The larvae (fig. 55, right) feed in the phloem, mining 
downward and commonly entering a large root by fall. The second 
summer they continue feeding and excavating galleries and push- 
ing out coarse frass through holes made near the egg slits. The 
base of infested trees may be practically riddled by their tunnels. 
Two years are required to complete the life cycle (533). 
Cottonwoods planted on poor sites such as clay soils and sand 
flats in Mississippi may be killed, or they may be broken off at 
the ground by the wind. Damage may also be serious in natural 
stands growing on poor sites (538). 
The sugar maple borer, Glycobius speciosus (Say), breeds in 
living sugar maples in southern Canada and throughout the 
Northeastern States, westward to the Lake States and southward 
through the Appalachians. The adult is robust, velvety black, and 
about 27 mm. long. The head is clothed with yellow fine hairs; the 
pronotum is much wider than long, constricted at the base, and 
marked with two parallel yellow bands on each side. Each elytron 
bears five yellow bands, with those at the front forming a W- 
shaped design. Full grown larvae reach a length of 50 mm. 
Eggs are deposited in bark crevices, under bark scales, or 
around wounds, usually during July and August. The larvae feed 
beneath the bark. Their tunnels run more or less across the grain 
and cut deep channels in the wood. The winter is spent as a larva 
in a chamber formed in the sapwood. The following spring, feed- 
ing is resumed, with the larva cutting a larger gallery in the sap- 
wood. The mature larva bores deep into the wood and constructs 
a pupal cell at the end of its tunnel. Prior to entering the cell, 
it cuts an exit hole through which the adult emerges. During this 
activity, they push considerable quantities of sawdust to the out- 
side. Pupation occurs in the spring, and the life cycle requires 2 
years (703). 
The presence of transverse ridges or elevations on the large 
limbs or trunks of sugar maple, or of sawdust-like frass and 
moisture on the bark, are evidence of attack by the sugar maple 
borer. The bark over ridges is pushed outward at an angle or is 
broken up in the form of cracks, some of which may completely 
girdle the tree. These cracked, swollen areas often resemble cank- 
ers or galls. Damage is generally most severe to shade trees or 
to trees growing in open stands or along streams. Infestations 
in the forest appear to be heaviest in open second growth stands, 
or in heavily grazed, understocked stands. The growing of sugar 
maple in well-stocked groups, the avoidance of overgrazing, and 
the removal and burning of infested dead limbs and trees before 
adult emergence in the spring should be helpful in reducing 
losses (644). Borers in shade trees can be killed by the injection 
of a fumigant into their tunnels or by piercing their bodies with 
a wire pushed into their tunnels. 
The red oak borer, Hnaphalodes rufulus (Hald.) (=Romaleum 
rufulum), breeds in the trunks of living oaks in southern Canada 
and throughout eastern United States, west to Minnesota, Iowa, 
and Texas. In the Central States, red, scarlet, and black oaks are 
180 
