The southern pine beetle is the most harmful insect pest to Mississippi forests. This is evidenced by its scientific name, which is translated to mean “tree killer”.
There is good news and bad news relating to the southern pine beetle. The good news is that Mississippi Forestry Commission (MFC) state-wide surveys have indicated a low level of southern pine beetle activity in 2020. The bad news is that the “tree killers” have been detected in a Pontotoc County this summer.
It is important for timberland owners to stay diligent, even during years without large scale outbreaks. I will discuss southern pine beetle detection, prevention, and control measures. The references used include the Mississippi State University Extension Service publication “Southern Pine Beetle in Mississippi an Overview”and the MFC publication, “Mississippi Experiences Decline in Southern Pine Beetle Numbers”.
Southern Pine Beetle
Southern pine beetles are native insects. The adult beetles are generally about the size of a grain of rice. They are attracted primarily to slow growing and weakened pine stands.
The adult beetles, their larvae, and the blue stain fungi they introduce contribute to the death of pine trees. The females lay eggs as they construct “S” shaped galleries inside the bark of the tree. After the galleries are constructed, the adults bore out and attack again. Once the eggs hatch and the larvae mature, they exit and fly to another location to begin an attack.
If temperatures are above 55 degrees Fahrenheit the beetles continue to feed, grow, and mature even during the winter. Southern pine beetles can have up to seven generations per year, depending on weather conditions.
The center of southern pine beetle spots can be identified by tree crowns that have red needles. The color of the tree crowns transition to yellow and then green toward the edges of the spots.
The presence of pitch tubes also indicates southern pine beetle attacks. They have the appearance of popcorn shaped balls on the outside of the trees.
The last way to identify southern pine beetle attacked trees is by removing the bark to observe the “S” shaped galleries left by the beetles and their larvae.
Timely thinning and harvesting mature pine stands reduce the probability of southern pine beetle damage. These practices mitigate attacks by maintaining tree health and vigor.
For help determining if your pine stands need thinning, contact me at 662-489-3910. You can also refer to Mississippi State University Publication 2260 “Are My Pine Trees Ready to Thin?”
If southern pine beetle spots are detected, application of timely control practices are needed. Three methods of control include salvage removal, cut and leave (fell the trees toward the center of the spot), and pile and burn. It is important to remove the trees that are being attacked along with several adjacent trees to form a buffer around the spot.
Be aware that the threat of southern pine beetle attacks is real in Pontotoc County. It is important to check and thin your pine stands at the appropriate times.