Photo by Arlo Kane
From the USDA's Natural Resources Conservation Service:
Prescribed burns in longleaf pine forests reduce tick numbers
By Arlo Kane
Regional biologist, Landowner Assistance Program
Florida Fish and Wildlife Conservation Commission
Can a well-managed Florida longleaf pine forest reduce the number of disease-carrying ticks? The answer is yes, according to a recent study. Long-term regular use of prescribed burns on land with longleaf pines can result in fewer of those nasty, biting, disease-bearing ticks.
The implications for landowners and managers are quite interesting.
Let’s start with the increased number and type of tick-borne diseases in recent years: Lyme disease, Rocky Mountain spotted fever, erlichiosis, Southern Tick Associated Rash Illness and the emerging heartland virus.
Ticks are all too common in Florida’s woodlands, especially in summertime. You are most likely to pick up ticks when you’re walking in an upland hardwood forest. Hardwood forests typically have closed canopies and plenty of leaf litter on the ground, compared to open canopied pine forests with diverse ground cover. The hardwood forest floor offers ticks better moisture retention and therefore survival.
Many hardwood forests are important natural habitats for a variety of wildlife. However, some hardwood forests occur because fire has been excluded on the land for a long time. Fires, especially spring and summer fires, help keep hardwood saplings in check. Historically, many fires in Florida were initiated by lightning strikes during summer thunderstorms, and these hot fires would kill hardwoods. In the past, Florida was more of a savanna, a grassland with scattered trees, with hardwoods mostly in the drains and bottoms where they were protected from fire. Longleaf pine dominated these savannas, the most fire-adapted pine species in Florida. Longleaf pine trees are very tolerant of prescribed burning throughout their lifetime. Native Americans burned the woods for many reasons, including control of insects like ticks.
But does burning really control tick numbers?
Past short-term studies found only temporary benefits from prescribed burning on infestations. But the results are quite different from a long-term research project published in November, 2014. Looking at 21 properties in southwest Georgia and northwest Florida, researchers compared the lands with a history of regular prescribed burns for more than 10 years with lands that had not been prescribed burned for at least 10 years. The results clearly demonstrated that long-term burning significantly reduced tick numbers.
Regularly burned areas seemed to deplete source populations of ticks and resulted in a long-term reduction in tick numbers. That’s good news for anyone who spends time in the woods. While the Florida Fish and Wildlife Conservation Commission often focuses on the benefits of prescribed burning for wildlife and wildlife habitats, as well as reduction of wildfires, here is a very direct benefit for people. The reduction of tick populations has important implications for public health, and prescribed burning is a cost-effective method that can be applied on a landscape level. Reducing tick numbers potentially will reduce the risk of tick-borne diseases.
The pine species most adapted to frequent prescribed burning and the one that can be burned as early as one year after planting? It is the longleaf pine. Discovering this management practice is bad news for ticks is just one more reason to consider longleaf when planting a pine species in Florida.
For information on longleaf pine technical assistance or cost-share programs, contact a Landowner Assistance Program biologist with the Florida Fish and Wildlife Conservation Commission at MyFWC.com/lap. The Natural Resources Conservation Service also provides technical and financial assistance to manage and restore longleaf pine. Learn more at your local USDA service center.