Anatomy of a Growing Season Burn

June 19, 2025

Burning in late spring or summer can be challenging, requiring careful planning and compliance with strict regulations in many parts of South Georgia. On a small farm in southeast Georgia, a successful growing season burn was recently completed.

Groundcover Vegetation

The property contains ag fields, pastures, ponds, cypress drains, planted pine stands, and a special 10-acre stand of mature longleaf pine. The understory is very typical of southern rough consisting of a moderate shrub and grass layer of gallberry, saw palmetto, wiregrass, broom sage, and other small forbs conducive to wildlife.

The longleaf stand has been burned on three-year rotation since 2000 but always in the winter. After years of apprehension, it was finally decided to conduct a growing season burn. The goals for the burn were purely wildlife habitat improvement and wiregrass enhancement.

Fire Weather

Favorable weather conditions for burning this stand include: a steady 5-10 mph west wind, humidity between 50%-75%, temperature less than 90 degrees, and a smoke dispersion index higher than 40.

There were still concerns about crown scorch and lingering smoke, but knowing that a transport wind of 10-15 mph will take care of those issues, the concerns were quickly lifted.

Fortunately, a much-needed three-inch rain fell a few days prior, assuring adequate ground moisture.

With favorable conditions finally matching the burn plan in mid-May, a burn permit was obtained.

Prescribed Fire Terms

Growing Season Burn - Control burns conducted during the late spring to early fall when plants are actively growing.

Black Line - Refers to a cleared area of burned vegetation along the perimeter of a burn unit to act as a fire break.

Firing Techniques

TEST FIRE

A small test fire was ignited around 11:00am. The green vegetation quickly began to burn and spread according to expectations.

BACKING FIRE

After a few minutes of observation, a backing fire (or downwind fire) was used to blacken approximately 20 feet off the east fire break.

Initially, attempts to use strip-heading fire and point source fires on a grid pattern of every 10 feet caused the fire intensity to be greater than desired.

Due to the steady west winds, burning techniques were adjusted to use flanking fire. Stringing 40-foot strips straight into the wind, roughly 50 feet apart, kept the fire much more manageable.

This method kept flame lengths minimal and helped move the fire across the landscape at a quicker rate.

This pattern was continued throughout the burn which lasted roughly three hours. There were a few hot spots around some of the felled trees from the Hurricane Helene, but “all in all”, it was a successful burn.