(This is excerpted from a July 10 blog from the Southern Group of State Foresters.)
Southern forests across the United States are encountering some significant challenges right now. These forests, known for their beauty, ecological significance and substantial economic impact, are facing various environmental and biological threats in 2024. From towering pines to sprawling oaks, our trees are facing issues that need attention and decisive action.
A key factor in addressing these challenges is the strong partnership between southern state forestry agencies, the USDA Forest Service and other key partners. Together, these collaborations are critical in implementing effective strategies and solutions. In this blog, we will explore the top four southern forest health threats of 2024, highlighting the critical issues and proactive measures being taken by our partners to combat them.
1. Drought/Ips bark beetles
In the late summer and fall of 2023, a “hot drought,” which is characterized by little to no precipitation combined with maximum temperatures 5-10 degrees above normal, impacted Mississippi and Louisiana. Across these states, pine trees began dying in response to outbreaks of Ips bark beetles during the late fall and winter months of 2023 and into 2024. Ips bark beetles are less aggressive than the more well-known southern pine beetle, but they can become a serious problem when pines are vulnerable to pests during periods of sustained environmental stress.
As a result, an estimated 150,000 acres of pine mortality occurred across these two states, although some of the mortality, about 20,000 acres, was attributed to wildfire. Most of the tree mortality that was accounted for was loblolly pine in plantation or mixed forest settings, but there were also huge economic impacts to urban forest landscapes, which remain under-documented. This includes impacts to street and yard trees, woodlots, parks, cemeteries, golf courses and transportation/powerline rights-of-way areas. ....
2. Southern Pine Beetle
Southern Pine Beetle (SPB) is a native bark beetle in the South. Most landowners and forest managers are familiar with SPB because it can have a tremendous impact on southern yellow pine during outbreak. While we have seen several regionally significant outbreaks and impacts over the years, based on observed activity in autumn 2023 and results from the annual spring trapping survey conducted by state forestry agencies and the USDA Forest Service, there is a high likelihood that SPB activity could be significant this year. Several states could have moderate to high activity in 2024 – particularly Alabama, Georgia, Mississippi and South Carolina. ...
3. Spongy Moth
Spongy moth, an exotic species formerly known as gypsy moth, commonly reaches outbreak numbers every eight to twelve years in the United States. Spongy moth caterpillars can feed on hundreds of species of trees and shrubs, but particularly target oak trees. When caterpillars repeatedly eat all the leaves on trees during outbreaks, trees can die. In 2023, spongy moth outbreaks impacted 1.3 million acres in 13 states across the Midwestern and Eastern U.S.
In northern Virginia, spongy moth outbreaks have been impacting the area since 2022. The outbreak has already killed mature trees across all land ownerships. Because of the high population densities, caterpillars can also be a nuisance to homeowners and forest-goers as they move between trees. Furthermore, the long hairs on the caterpillars can cause allergic reactions to some people. ...
4. Brown Spot Needle Blight
Brown spot needle blight (BSNB) is emerging needle disease on loblolly pines in the southeastern states. The fungal pathogen, Lecanosticta acicola, has been known to cause severe damage on longleaf pines at grass stage, but is now becoming a serious threat to health of loblolly pines since 2016. BSNB on loblolly pines has been confirmed in 115 counties from nine states (AL, AR, FL, GA, LA, MS, SC, TN, and TX) while most severe cases were reported from AL, AR, LA, and MS with landscape scale damages on mature trees and/or localized damages on younger trees in commercial stands. Mortality and growth loss have been observed from the younger trees after repeated infections over multiple growing seasons. Infestations of Ips bark beetles also have been observed on the trees weakened by BSNB....
Southern forests are at a crossroads. The combined impact of drought, pest outbreaks and invasive species poses a serious threat to their health and sustainability. However, through the concerted efforts of federal and state agencies, key partners and private landowners, combined with innovative technologies and active forest management practices, there is hope for mitigating these threats. By staying informed and proactive, we can ensure that southern forests continue to thrive for generations to come.