Various chemicals such as fumigants, contact poisons, and baits have been used to control the leaf-cutting ants with varying success. No natural control has yet been found.
SOUTHERN PINE BEETLE, Dendroctonus frontalis (Zimm.)
Probably no other insect is of more concern to managers of southern pine forests than the southern pine beetle. Loblolly and shortleaf pine seem to be preferred hosts, but all of the southern pines may be attacked wherever they occur in North and Central America.
Adult beetles are about the size of a grain of rice, stout and reddish-brown in color. While they commonly attack lightning-struck or weakened trees, they can also quickly build up to high populations capable of successfully attacking healthy trees during periods favorable to their development. Adult beetles bore directly through the bark, mate, and the females begin to excavate S-shaped egg galleries in the inner bark. Eggs are deposited in niches on either side of these galleries and hatch into small legless grubs within four to nine days. The grubs mine for a short distance before boring into the outer bark where they pupate. There are from three to seven generations per year depending on locality and weather. Drought seems to be associated with major outbreaks of this insect.
Adults of the black turpentine beetle, the southern pine beetle and three species of Ips engraver beetles.
Control includes rapid salvage and utilization of infested trees and piling and burning of infested material. Outbreaks usually subside with the advent of unfavorable weather and improved host vigor.
Southern pine beetle larval galleries.
