Playing an active role in nature by selectively finding mature, stressed or damaged pines in the forest, Pine Bark Beetles are attracted to the odor produced by wind-thrown trees and trees damaged or killed by nature or man. Living pine trees are infested when susceptible to drought, age, disease, root rot, fire, hail, lightening, or other insects. Once a colonized group of beetles infest a tree, they produce special chemicals that, combined with the trees odor, “calls” in a large number of beetles that “mass attack” a tree. They also produce another chemical that prevents the arrival of other beetles preventing overpopulation. Pine Bark Beetles also infest fresh logs and sometimes healthy trees. If the tree is healthy, it produces a large amount of sap that flows through the tunnels dug by the beetles then hardens on the outside of the bark killing any beetles it picks up along the way. The hardening of the sap on the outside of the tree is also known as “pitch tubes.” If these pitch tubes are not seen on the outside of the tree, attacks are also indicated by brown boring dust either in the bark crevices or at the base of the tree.

Identification, Biology and Management of Beetles

More commonly known as the Black Turpentine Beetle (BTB), the Southern Pine Beetle (SPB), and the IPS Engraver Beetle (IEB), Pine Bark Beetles do more damage to timber in the south than any other type of insect by boring through the outer bark and feeding within soft inner bark of pine trees. Each species of beetle attacks a specific part of the pine tree. IPS Engraver Beetles can attack the whole tree, BTB Black Turpentine Beetles attack the lower 8-10 ft portion of the trunk, and SPB Southern Pine Beetles attack from the middle of the tree to the middle crown.

Black Turpentine Beetles (BTB) Dendroctonus terebrans have rounded abdomens, are dark reddish brown to black and are usually ¼ inches long. BTB’s are the largest beetles found in Georgia . The female beetles lay her eggs along the inner-sides of the tunnels that are burrowed from point of entry in a downward fashion parallel to the grain of the wood. The larvae are legless, creamy white, and crescent shaped with glossy, reddish brown head capsules. The larvae feed and follow the same tunnels the adults created before they pupate in bark to emerge as adults ready to infest another tree and begin the cycle again. Fully grown larvae are ½ inches long with life cycle that lasts 10-16 weeks depending on temperature.

Southern Pine Beetles (SPB) Dendroctonus frontalis have long rounded abdomens, are brownish to black in color and are usually 1/8 inches long. SPB’s are the most important bark pests in the Southern United States occurring from Delaware south to Florida and west to Texas . The female beetles lay her eggs in S shaped forms along the burrowing tunnels that are also packed with brown feces and boring dust. Pitch tubes produced by the pines infested with Southern Pine Beetles are usually less than ½ inch and generally located within the bark crevices. Weak trees that are attacked by these beetles show signs of brown boring dust in its crevices or on spider webs located on the trees. Infestation occurs on the trunks of trees from base to crown. Southern Pine Beetles carry and leave on the trees the strain of Blue Stain Fungi that damages and disrupts the water flow to the crown thus killing the tree. Trees infested with the SPB even when the larvae are killed by insecticide cannot be saved.

IPS Engraver Beetles (IEB) are the most important beetle and cause the most damage in Florida . They are cylindrical in shape, are dark brown to black in color and are usually 0.1-0.3 inches long. Their rear ends are sunken or “chopped off” with four to six spines along each side. The male adults usually begin the attack on the trees with the female laying eggs shaped roughly like Y, H, or I usually parallel to the grain of the sapwood. The pitch tubes produced by the attacked tree are less than ½ inch long and look very similar to the attacks of the Southern Pine Beetle. The only noticeable presence of an attack on weak trees is the brown boring dust in bark crevices and on the spider webs attached to the trees. The life cycle of the IEB is 25 days depending on temperature. IPS Engraver Beetles also carry the strain of Blue Stain Fungi, thus the infested tree cannot be saved even when the larvae are treated. ISP Engraver Beetles include these different species within its classification: Small Southern Pine Engraver, Six Spined IPS, Eastern Five-Spined IPS, and the Pine Engraver.

Small Southern Pine Engraver Ips avulsus is the smallest of IPS beetles. It is 0.1 inches long, has four small spines on each side of the sunken area on their hind ends, and breed in all species of pines. These beetles prefer thin bark on cut tree limbs and tops, but can attack young trees and the top of large living trees.

Six Spined IPS Ips calligraphus is the largest of the IPS species between 0.15-0.25 inches long with six spines on each side of the sunken area at the rear end. These beetles infest the lower trunk in pines greater than 15 cm in diameter and breed in trunks, stumps, or large limbs of fallen trees. They can also attack healthy trees. The Six Spined IPS is usually the first species to attack drought stricken trees. The adult female lays her eggs in chambers running up and down, grooving both bark and wood.

Eastern Five-Spined IPS Ips grandicollis is commonly found in Georgia. With a length of 0.1-0.2 inches long and five spines on each side of a sunken rear end, it commonly infests middle parts of the open trunk as well as large limbs in the crown.

Pine Engraver Beetle Ips pini is the most damaging of IPS beetles, only found in North Georgia usually attacking Eastern White Pines and creating a wide area of outbreaks. The adult beetles are brown to black, 0.14-0.2 inches long and have four teeth on each side of its rear end. The eggs that are produced deeply scar the sapwood of the pine.

Beetle Infestation Signs

Some beetle species spread rapidly to other trees adjacent to the infected one, therefore it is extremely important to recognize the infestation signs of bark beetle attack and to identify the type of beetle causing the attack.

Other trees that can become infested include many high value yard, ornamental, seed orchard, and naval store pines.

The first sign of an infested tree includes yellowing or reddening tree crowns. Usually not noticeable until the tree is already infested or dead and beetles have completed their cycle and left the tree. (Tree crowns are the part of the tree above the trunk and include most or all of the foliage.) You might also notice white, saw-dust like “boring dust” at the base of the tree produced by ambrosia beetles who attack the diseased tree after it is weakened by bark beetles.

The first step to control the outbreak of Pine Bark Beetles is to find signs of attacks on the trees itself, not just changes in crown color. Identify the beetles by removing bark and examining the adults. Locate and mark all attacked trees, then apply chemicals in a timely manner to all trees that are attacked. Thoroughly saturate bark of entire trunk

Remember that trees attacked by Southern Pine Beetles and IPS Engraver Beetles cannot be saved, therefore should not be treated with insecticides. These trees need to be cut down and removed to prevent infestations of other weak trees. Once removed, use the insecticide on healthy trees to prevent further attacks. Only trees infested by the Black Turpentine Beetle have a chance to survive if treated. If BTB attacks are present and crown fade is not visible, apply insecticide on bottom of trunk 8-10 feet. It is advised to treat lower trunk portions of surrounding non-infected trees.

Treatment: Professional Strength Permethrin Tree spray, Permethrin Pro, Dragnet, Bifenthrin Products - Onyx, Talstar.

Our thanks to Lani Powell whose research made this information page possible!

Household Pest Control Pesticides Pests Site Map Talstar One Permethrin Pine Bark Beetles

Pine Bark Beetles

Order: Coleoptera Family: Scolytidae

Order: Coleoptera
Family: Scolytidae