Southern Pine Bark Beetle
Southern Pine Beetle (Dendroctonus frontalis), along with several other bark beetles (black turpentine beetle and three Ips engraver beetles), are known to attack and kill southern yellow pines during periods of environmental stress. These beetles bore into the cambium in large numbers, and disrupt nutrient and water movement, thus killing the tree. Several of these species also introduce a fungus, known as blue stain, which aid in killing a tree by clogging its vascular systems.
Pine bark beetle outbreaks are being fueled by drought conditions and other environmental stress factors such as wildfires and storms throughout the southeastern United States. The Southern Pine Beetle originated in the southeastern United States, but has now migrated as far north as Massachusetts.
Common Symptoms
The southern pine beetle (SPB) will attack healthy pines, but the other bark beetles more often colonize severe stressed trees. Individually attacked trees may look faded or have mixed tan and green needles progressing to red, followed by tree death over several weeks. SPB will create cream to red colored, dime-sized pitch tubes on the lower bole (6 feet and higher) of the tree. The black turpentine beetle create large (1-2 in diameter) pitch tube on the trunk from 3 feet height to the ground. Attacks by Ips engravers can occur from the ground to small branches in the upper crown and usually produce granular boring dust that accumulate in bark cracks and spider webs. Most of these beetles carry a fungus that serves as a food base for young larvae. The introduced fungus severely inhibited water transport and hastens tree mortality.
Treatments
A trunk injection of TREE-äge® G4 or TREE-age R10 will provide up to two years of protection against bark beetle attack. Preventative treatment is best, as trees with existing beetle infestations are less likely to survive. In areas where beetles carry the blue stain fungus, it is recommended that Propizol® systemic fungicide be added as a sequential treatment to eliminate additional stress from the fungus.
References And Photo Credits
Southern pine bark beetles taken by John L. Foltz, University of Florida, www.bugwood.com
Southern pine beetle pitch tubes taken by Tim Tigner, Virginia Department of Forestry, Bugwood.org
Black turpentine beetle pitch tubes taken by Ronald F. Billings, Texas A&M Forest Service, Bugwood.org
Ips engraver beetle killed pine taken by Ronald F. Billings, Texas A&M Forest Service, Bugwood.org
