Southern Pine Beetle: Identifying Characteristics
Identifying the injury:
Needles of infected trees turn from green to yellow to red to brown and then fall off the tree. Early signs of attack include brownish-orange boring dust from the holes and tunnels around the tree. Yellowish-white pitch tubes may be present on the outer bark of the tree. The winding, S-shaped galleries are filled with boring dust and frass. These galleries are distinct from the Y or H-shaped galleries of the Ips beetles. Exit holes will be in the outer bark and resemble holes made by birdshot. Southern pine beetle attack is usually accompanied by attacks from other bark beetles and a variety of insects that are attracted to dying trees. Consequently, the distinctive S-shaped galleries may not be clearly seen unless the inner bark is inspected early on in the attack, before the attack of numerous other insects that follow the southern pine beetle.
Identifying the insect:
Adult southern pine beetles are 2 to 4 mm long and brown to black in color. The back section is round and spineless, unlike the Ips beetle of the same size and color, with its scooped out, spiny back section. Fully-grown larvae are the same size as adults but are yellowish-white with reddish heads and are legless. Pupae are pure white and the same size as adults.
Susceptible trees:
The southern pine beetle can attack any southern pine. Preferred hosts are loblolly, shortleaf, pond, and Virginia pine. In Florida, the southern pine beetle also likes spruce and sand pine as hosts. Slash and longleaf pine are the least susceptible pine species but even they can be attacked during outbreaks.