slender, metallic blue or green, has light brown legs, and is about 
9 mm. long. Dry scales over damaged areas of bark peel off. 
Oeme rigida (Say) breeds in dead and dying cypress and juni- 
per throughout eastern United States. The adult is light to dark 
brown and between 12 and 22 mm. in length. Eggs are deposited 
beneath bark scales and the larva feeds beneath the bark and in 
the wood, exuding large quantities of granular frass. Deadened 
cypress and rustic work constructed from improperly seasoned 
wood are often severely damaged, causing the bark to peel off and 
sometimes causing destruction of pieces of wood up to 3 inches in 
diameter. 
The genus Prionus Geoff. consists of a number of species of 
robust, black or brownish-black, shiny beetles from 25 to 45 mm. 
long. The antennae have from 12 to 27 segments and are heavy 
and imbricated in the male. There are three spines, or teeth, on 
each side of the prothorax. Several species are known to feed in 
the roots of a wide variety of living fruit, forest, and shade trees 
in eastern United States. Root rots, such as Armillaria, and 
various species of secondary boring insects often attack the dam- 
aged roots and kill the trees. Mature trees growing in open 
stands, in well-drained gravelly soil and hillsides, in pastures, and 
in heavily used recreation areas are especially subject to attack. 
Small trees and shrubbery are occasionally killed by borers that 
cut off their roots at the ground line. 
The broad-necked root borer, Prionus laticollis (Drury), breeds 
in the roots of a wide variety of trees and shrubs in eastern United 
States, mostly hardwoods. Oak, poplar, chestnut, and basswood are 
especially favored. Infestations have also been recorded in the 
logs and stumps of all the above species. The adult is dark- 
brown, shining, and up to 45 mm. long. The head is depressed 
between the eyes; the antennae of the male are shorter than the 
body; and the base of the pronotum is as wide as the elytra. Full- 
grown larvae may reach a length of 75 mm. Eggs are deposited 
in groups on the ground and the young larvae crawl to the roots 
to feed. At first, they feed in the bark, but soon enter the root 
which is completely hollowed out and occasionally severed. They 
move from root to root through the soil, feeding on the surfaces 
of smaller roots as they go and causing many injuries or wounds. 
Mature larvae come to within 3 to 5 inches of the soil surface in 
the spring and form oval, compact cells in which to pupate. The 
life cycle is believed to require 3 years. This species seldom causes 
substantial damage in the forest. 
The tile-horned prionus, Prionus imbricornis (L.), occurs 
throughout much of eastern United States and breeds in the living 
roots of oak, chestnut, pear, and various herbaceous plants. 
Adults (fig. 68) are dark brown, shiny and up to 37 mm. long. 
Male antennae are 18- to 22-jointed, and the segments overlap. 
Eggs are deposited in groups in the soil around the base of the 
tree. Larval habits are similar to those of the broad-necked root 
borer. The life cycle requires at least 3 years. 
Prionus pocularis Dalm. breeds in decaying coniferous logs and 
stumps in the Central, Middle Atlantic and Southern States. 
Adults are light brown, shiny, and about 42 mm. long. The elytra 
are densely punctured. 
200 
