Our cool weather can make the invasion of the Southern Pine Beetle even worse.

Our warming climate is leading to the expanded range of many species, contributing to the problem of invasive species in our region. Southern Pine Beetles (SPB), whose natural habitat is in the southeast, were discovered in Suffolk County New York in October, 2014. Since then they have expanded north to at least Albany.

This beetle attacks all pine trees and may also attack hemlocks and spruce. Infected trees die typically within 2-4 months from infestation. Details of the New York infestation can be found on the DEC site here.

Unfortunately, cooler weather in New York may increase the impact of this invasion according to a new study from Dartmouth College and published in Oecologia. The study reveals that the colder fall and winter temperatures in New York and other northern states influences the growth and development of immature beetles leading to a more synchronized emergence of adults with the arrival of spring.

“Climate change is not only giving this destructive species new territory to prey on, it’s creating a more lethal pest that can wreak havoc on forests,” said Jeffrey Lombardo, who conducted the research as a PhD candidate at Dartmouth.

The beetles kill trees by attacking in large numbers. The synchronized emergence caused by the colder fall and winter means that more beetles attack any given tree, resulting in higher tree mortality and a larger generation of beetles for the next season.

Pine beetle entering a pitch tube

“This research gives us a more sophisticated understanding of how temperature differences impact a species that has moved beyond its traditional range,” said Matthew Ayres, a professor of biology at Dartmouth, and a coauthor of the study.

What are the signs of an infestation?

• Pitch tubes, or popcorn-shaped clumps of resin on the exterior of the bark
• Shotgun patterned holes on the exterior of the bark
• S-shaped tunnels under the bark
• Pine trees that have recently died, characterized by reddish-brown needles

Eradication of this pest is not feasible because it has become widespread, moves quickly, and is present in neighboring states. As a result, forest health management conducted by the State is focused on protecting large forested blocks and unique habitats, such as the Core Preservation Area of the Long Island Central Pine Barrens Preserve.

Areas north of Long Island will continue to be monitored for early detection of SPB with traps, aerial surveys, and ground surveys.

Please monitor pine trees in your area for potential infestation. Reporting with iMapInvasives will help us to #StopTheInvasion