April 8, 2011

University of Arkansas, Division of Agriculture

Turfgrass Science Program (http://turf.uark.edu) – Turf Tips

Burning Bermudagrass Will Enhance Spring Green-up

Well, my turf tip about burning lawns did not get a strong response from Dr. Patton, but my good friend and colleague, Dennis Martin, at Oklahoma State, wanted to offer some additional insight about fires and turf. Since he is from the land of grasslands and grass fires, I will bow to his expertise!!

Mike Richardson

Hello Mike: Thanks for the article and images from the accidental fire in the dormant warm-season turfgrass stand at your facility. Looks like your stand had a rapid greenup and recovery of stand density.

Yes, turfgrass lawn or field burning can provide several benefits including increased soil temperatures early in the season (due to reduced surface reflectivity), improved early season greenup, reduced over-wintering disease inoculum, decreased amount of organic debris present that may interfere with seed harvest, and increased nutrient recycling and suppression of certain woody and broadleaf weeds. Unfortunately on some sites if adequate soil moisture and nutrients are not present following the burn and if strong winds or sudden heavy rains occur on steep slopes, increased soil erosion can occur following the burn.

Besides the obvious risk (fire) to surrounding areas, I have a few personal observations of negative impacts from burning in seed and sod production areas. Interested parties may wish to perform some investigation to determine if these observations apply to their situation. My observations have been:

1. in the case of buffalograss, a late winter/early spring burn:
a. can delay flowering relative to non-burned areas. This may delay the date of the first possible harvest of burs (seed). This may cause problems under dryland (non-irrigated) seed production conditions if a Mediterranean type climate is present. However, under conditions of irrigation, the delayed time of flowering and thus harvest may not be a problem.

b. results in substantial mortality of buffalograss stolons in sod production which may eliminate the option of an early harvest cycle and push the harvest into mid summer when transplant shock may be substantial greater. Buffalograss is "challenged" when it comes to sod tensile strength, even under the best of growing conditions. I have provided an image of a burned over lawn (at 7 days after the fire) of a female buffalograss clone. Note the high mortality of stolons after the fire.

2. in the case of bermudagrass, a late winter/early spring burn:
a. causes significant stolon mortality and if there are few to no rhizomes to provide sod tensile strength, can lead to a significant delay in days to first suitable harvest in the year of the burn (an extra 45 days). Many stolons overwinter to provide sod strength for early season bermudagrass harvest but they may be damaged if a burn has been conducted.

b. may cause aesthetic issues in early season harvested sod

c. may prove messy (black soot) when handling and installing early-season harvested sod.


Thanks for the interesting article and great food for discussion!

Dennis

Dennis Martin, PhD
Professor & Turfgrass Extension/Research Specialist
Oklahoma State University

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