Late Season Burning: A Tool for Range Management
Colin Tobin, range management
With the dog days of summer coming to an end, we can finally “relax” and focus on other parts of the operation, such as harvest, weaning, fall calving, fall planting, and field work. Prescribed burning may deserve a place on the late summer/fall to-do list. Though traditionally associated with springtime, late season burning can provide advantages in managing invasive plants while maintaining rangeland diversity.
Spring burning has been part of Flint Hills grazing management since the late 1800’s, with a transition in the 1970’s and 80s to annual spring burning coupled with intensive early stocking of yearling cattle. Removing old plant growth promotes uniform grazing, shifts plant growth curves, and supports improved gain efficiency of stocker cattle. Depending on management objectives, moving prescribed burns later in the growing season may provide producers with another useful tool.
Late-season burning generally refers to burning during the latter part of the growing season and even into Fall. Several studies from K-State have evaluated burns conducted from August to October. Although grouped into the same term for this article, burning dates shouldn’t be interchangeable. Burning during August allows more time for regrowth before dormancy, while a fall burn reduces plant recovery time and regrowth available for winter grazing. Additionally, planning burning for late season burns will require attention to available fuel, current and expected weather, and the operation’s needs.
Covering approximately 500,000 acres in Kansas, sericea lespedeza degrades native rangelands as it has low grazing palatability to cattle due to condensed tannin concentrations. Additionally, spring fires have been shown to stimulate germination1. However, research from the Flint Hills has shown a reduction in standing biomass, seed production, and frequency with August and September burns compared to spring burns. Also, species diversity, and native forb and native shrub cover increased with late season burns compared to spring burns2,3. Because sericea lespedeza, and other invasive species seed remains viable in the soil for years, late-season burning won’t act as a one-time eradication treatment but rather a suppression strategy.
The potential benefits of late season burning aren’t limited to sericea lespedeza. A single September 2006 burn in central Texas reduced the relative frequency of yellow bluestem from 74% to 9% in 2007 and remained comparably lower through 20094. Also, biannual fall burnings near Stillwater, OK, halted juniper encroachment over the course of 13 years5. Late season burn may help suppress Old World bluestems and woody plants, but it should not be viewed as a stand-alone treatment. Repeated fire, targeted herbicide application, grazing, or reseeding may be needed to achieve long-term control and restore native vegetation.
Spring burning remains valuable when maximizing early-season forage quality and stocker cattle gain is the primary objective. However, burning in August or September may provide greater benefits when controlling invasive species encroachment is the priority. Producers must weigh those benefits against the loss of standing fall forage, reduced time for plant regrowth, and the potential for modest reductions in subsequent cattle gain. Starting with a portion of the operation may provide a practical way to evaluate the response. The appropriate time to burn should be determined not by tradition alone, but by what the producer needs the fire to accomplish. Ultimately, the use of fire in spring or fall, in concert with herbicide and grazing management, can provide the most effective strategy to meet the unique land management needs of each operation.
1 Wong, B. M., G. R. Houseman, S. E. Hinman, and B. L. Foster. 2012. Targeting vulnerable life-stages of sericea lespedeza (Lespedeza cuneata) with prescribed burns. Invasive Plant Sci. Manage. 5:487493. doi:10.1614/ipsm-d-12-00002.1
2 Alexander, J. A., W. H. Fick, S. B. Ogden, D. A. Haukos, J. Lemmon, G. A. Gatson, and K. C. Olson. 2021. Effects of prescribed fire timing on vigor of the invasive forb sericea lespedeza (Lespedeza cuneata), total forage biomass accumulation, plant-community composition, and native fauna on tallgrass prairie in the Kansas Flint Hills. Transl. Anim. Sci 5:1–16. doi:10.1093/tas/txab079
3 Duncan, Z. M., A. J. Tajchman, J. Lemmon, W. R. Hollebeck, D. A. Blasi, W. H. Fick, and K. C. Olson. 2023. A 6-yr evaluation of prescribed-fire timing on yearling cattle growth performance and plant community dynamics on native tallgrass prairie in the Kansas Flint Hills. Translational Animal Science. 7. doi:https://doi.org/10.1093/tas/txad129.
4 Reemts, C. M., W. M. McCaw, T. A. Greene, and M. T. Simmons. 2019. Short-term control of an invasive C4 grass with latesummer fire. Rangeland Ecol. Manage. 72:182–188. doi:10.1016/j. rama.2018.07.009
5 Weir, J. R., and J. D. Scasta. 2017. Vegetation responses to season of fire in tallgrass prairie: a 13-year case study. Fire Ecol. 13:137–142. doi:10.4996/fireecology.130290241