branch. Privet hedges are subject to severe damage. The larval stage extends over a 
period of 2 years. 
Encyclops caerulea (Say), the oak-bark scaler, bores in the outer bark of living 
white oaks, yellow-poplar, maple, tupelo, black ash, and pignut hickory in the 
Eastern States. Dry scales peel off over damaged areas of bark. The adult is slender, 
metallic blue or green, has light-brown legs, and is 7 to 11 mm long. 
Oeme rigida rigida (Say) breeds in dead and dying baldcypress and juniper 
throughout the Eastern United States. The adult is light to dark brown and between 
16 to 20 mm in length. Eggs are deposited beneath bark scales and the larva feeds 
beneath the bark and in the wood, producing large quantities of granular frass. 
Deadened baldcypress 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 8 cm in diameter. 
The genus Prionus consists of a number of species of robust, black or brownish- 
biack, 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 the Eastern United States. 
Root rots, such as Armillaria mellea (Vahl ex Fr.) Kummer, and various species of 
secondary boring insects often attack the damaged roots and kill the trees. Mature 
trees growing in open stands, in well-drained gravelly soil and hillsides, in pastures, 
and in heavily used recreational areas are especially subject to attack. Small trees 
and shrubbery are occasionally killed by borers that cut off their roots at the ground 
line. 
Prionus species have been found to be associated with declining pecan trees in 
Georgia and Alabama. Whether the larvae are primary or secondary invaders on 
pecan is unknown. There is no known adequate method for controlling the larvae or 
beetles (1/37). 
The broadnecked root borer, P. /aticollis (Drury), breeds in the roots of a wide 
variety of trees and shrubs in the Eastern United States. Mostly hardwoods are 
attacked, including oak, pecan, poplar, chestnut, and basswood. Infestations have 
also been recorded in the logs and stumps of all the above species. The adult is dark 
brown, shining, and 20 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 8 to 13 cm of the soil surface in the spring and form 
oval, compact cells in which to pupate. The life cycle requires 3 to 5 years. This 
species seldom causes substantial damage in the forest. 
The tilehorned prionus, P. imbricornis (L.), occurs throughout much of the 
Eastern United States and breeds in the living roots of oak, pecan, chestnut, pear, 
and various herbaceous plants. Adults (fig. 140) are dark brown, shiny, and 24 to 50 
mm long. Male antennae have 18 to 22 jointed segments that overlap. Eggs are 
deposited in groups in the soil around the base of the tree. Larval habits are similar 
to those of the broadnecked root borer. The life cycle requires 3 to 5 years. 
Prionus pocularis Dalman breeds in decaying pine logs and stumps throughout 
309 
