Southern Pine Beetles(Dendroctonus frontalis)Latin Name: Dendroctonus frontalis
Common Name: Southern Pine Beetles
Appearance:
Adults are cylindrical, stout to elongate in form.
Larvae are legless, crescent-shaped grubs with three thoracic and ten abdominal segments.
Females deposit their eggs on opposite ends of “s-shaped” tunnels in phloem tissue. Immature adults that have not yet emerged from the trees are light brown in hue.
The pupa is yellowish-white as well. It has the same shape as an adult, but the wing pads and legs are folded down, exposing the abdominal segments. The pupae range in length from 3 to 4 mm. Pupae and callow adults appear along with the outer bark in preparation for emergence.
Host plants:
frontalis feeds on a range of Pinus species. The commercially significant species of southern yellow pine is a key host in the southern United States. P. englemannii, P. leiophylla, and P. maximinoi are all significant hosts in Central America.
Territory:
The southern pine beetle, Dendroctonus frontalis, is a bark beetle native to the woods of the southern United States, Mexico, and Central America.
Damage caused by Dendroctonus frontalis:
The southern pine beetle (SPB), Dendroctonus frontalis Zimmermann, is the pine’s most damaging insect pest in the southern United States. In east Texas, it colonizes sensitive pine trees in large numbers, producing damage that leads to fast decline and death of afflicted trees, medically innocuous. Infested trees perish swiftly owing to gallery girdling and a blue stain fungus. Before dropping, the needles of infected pines become yellow, then crimson.
Life history and Habits:
Depending on the season, the time it takes from egg to adult spans 26 to 54 days. In Virginia, the beetles may have as few as three generations and seven generations in Texas. At all phases, the beetles spend the winter within trees. Adults begin to fly in the spring when the dogwoods blossom. Females descend on host trees at the height of 6.6-29.5 ft. (2-9 m), bore through the bark, and, if successful, generate a pheromone that draws men and females to attack the tree in mass. Females begin to construct egg galleries. Mating occurs in the gallery, which is followed by female egg-laying. Within 4 to 9 days, the eggs hatch into little larvae; before boring into the outer bark, the larvae mine for a short distance. Adults can reappear from galleries and attack fresh trees. Freshly attacked trees are frequently the center of interest within an infestation. As the infestation spreads, neighboring trees usually succumb to the attack, resulting in a cluster of trees emitting pheromones. As a result, infestations frequently spread in one or more directions.
