Pine Bark Beetles of Florida

Pine bark beetles are insects that normally attack stressed and dying pine trees, and usually do not infest trees that are otherwise healthy and vigorous. They feed and breed in the inner bark of pine trees, and introduce symbiotic fungi into the tree, often causing or hastening the death of the tree as a result. In natural forest settings, these native beetles serve an important function, by weeding out weak trees and freeing up resources for healthy individuals.

There are five native species of pine bark beetles that are important in Florida: three species of Ips engraver beetles (Ips calligraphus, I. grandicollis, and I. avulsus), and two species of Dendroctonus, including the southern pine beetle or SPB (D. frontalis), and the black turpentine beetle (D. terebrans). A dying pine may have multiple bark beetle species feeding in it.

The behavior and potential impact of these different types of pine bark beetles differ from one another in important ways, so it’s preferable to determine what species of bark beetles are primarily involved in an infestation before choosing a control strategy. For all of these species, the best approach is to prevent infestations from starting, by using management strategies that promote good tree health and vigor.

Ips Pine Engraver Beetles

Of these bark beetle species, the Ips engraver beetles are the most frequently observed in association with pine tree mortality in Florida. The three common species in Florida tend to infest different parts of the tree: I. calligraphus in large-diameter material near the bottom of a mature tree, I. grandicollis in the mid to upper bole (or lower bole of smaller trees), and I. avulses in small-diameter material in or near the crown. A healthy, vigorous pine tree is not likely to be susceptible to attack by Ips beetles, and they are normally restricted to colonizing pines that are already very stressed, damaged, or dead for other reasons. Unlike southern pine beetle (SPB) infestations, Ips infestations do not expand rapidly through aggressive tree-to-tree spread of the beetles. Thus, removal of infested trees does not necessarily reduce the probability of attack on neighboring trees.

Ips Pine Engraver Beetle Resources

• Ips Engraver Beetles [ 261.5 kB ]
• Ips Featured Creature Site (Univ. Fl.)

Black Turpentine Beetle (BTB)

The black turpentine beetle (Dendroctonus terebrans) is the largest of these pine bark beetle species. It attacks near the base of the tree, where the inner bark is thickest, and may also infest fresh stumps. BTB activity is often found in association with Ips and SPB infestations, and the beetles are attracted to stressed and injured trees. BTB is not usually known to spread aggressively or to kill healthy trees, and trees can sometimes recover from a limited number of attacks by this species.

Black Turpentine Beetles Resources

• Black Turpentine Beetle [ 131.9 kB ]
• BTB Featured Creature Site (Univ. Fl.)

Southern Pine Beetle (SPB)

Southern pine beetle (Dendroctonus frontalis) is perhaps the best-known pest of southern pines. Like Ips and black turpentine beetles, SPB normally attacks stressed and dying pine trees. Under certain environmental conditions, however, SPB outbreaks can occur, during which vast acreages of pines in both forests and residential landscapes are mass-attacked and killed. Florida has experienced devastating SPB outbreaks in the recent past. Historically, the range of SPB in the state has included only north and central Florida, and no SPB activity has been recorded south of Orange and Hernando Counties. Bark beetle activity observed in south Florida can most likely be attributed to Ips and black turpentine beetles.

 Southern Pine Beetle Resources

• Florida Forest Service's Southern Pine Beetle site