Landscape-level Effects of Thinning and Burning

Research Issue

Oak regeneration continues to be a problem in the Central Hardwoods region of the US. In the absence of regular fire (as was common before European settlement and fire regulatory agencies in the ~1920’s), the canopy closes and oak regeneration is often preempted by more shade-tolerant species like maples. The Fire and Fire Surrogates Study (FFS) is aimed to better understand the influence of multiple fires and thinning on oak regeneration. This research is a component of the FFS work in Ohio.

Our Research

We analyzed tree regeneration over seven years (2000-2006) on two sites (REMA and Zaleski), on a 50-m grid (242 plots) for “thin once-burn twice” and control treatments. The plots were assessed for Integrated Moisture Index, canopy openness, and woody vegetation composition and cover. In the process, we also developed a technique for monitoring relative measures of fire temperature with thermocouples and buried data loggers across the landscape, including the preparation of on-line animated fire sequences.   

Research Results 

• After 7 years, the “thin once-burn twice” treatment did provide opportunities for limited oak regeneration--time will tell whether regenerating oak will reach canopy. 
• Two prescribed fires were necessary to reduce the competition from maple regrowth. 
• Thin-burn treatments enhanced oak-hickory regeneration primarily on dry or intermediate sites with 8.5-19% canopy openness, and with at least 5000 oak-hickory seedlings/ha prior to treatments. If these factors were met, we calculate that roughly 50% of the area could become ‘competitive’ for oak-hickory in the next forest. (More information)


• Thermocouples with buried loggers were shown to provide an accurate method to inform fire managers of the relative fire intensities across the landscape. (More information)
• Animation of prescribed fires on Zaleski and REMAburns 

Iverson, L. R., T. F. Hutchinson, A. M. Prasad, and M. Peters. 2008. Thinning, fire, and oak regeneration across a hetergeneous landscape in the eastern U.S.: 7-year results. Forest Ecology and Management 255:3035-3050.

Iverson, Louis R.; Prasad, Anantha M.; Rebbeck, Joanne. 2004. A Comparison of the Integrated Moisture Index and the Topographic Wetness Index as Related to Two Years Of Soil Moisture Monitoring in Zaleski State Forest, Ohio. In: Yaussy, Daniel A.; Hix, David M.; Long, Robert P.; Goebel, P. Charles, eds. Proceedings, 14th Central Hardwood Forest Conference; 2004 March 16-19; Wooster, OH. Gen. Tech. Rep. NE-316. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northeastern Research Station: 515-517 

Iverson, Louis R.; Yaussy, Daniel A.; Rebbeck, Joanne; Hutchinson, Todd F.; Long, Robert P.; Prasad, Anantha M. 2004. A comparison of thermocouples and temperature paints to monitor spatial and temporal characteristics of landscape-scale prescribed fires. International Journal of Wildland Fire. 13: 311-322.

Iverson, LR, AM Prasad, TF Hutchinson, J. Rebbeck, and DA Yaussy. 2004. Fire and thinning in an Ohio oak forest: grid-point analysis of fire behavior, environmental conditions, and tree regeneration across a topographic moisture gradient. Pages 190-197  in M. Spetich, ed. Upland Oak Ecology Symposium: History, Current Conditions, and Sustainability. Southern Research Station, USDA Forest Service, Asheville, NC.  

Iverson, Louis R.; Hutchinson, Todd F. 2002. Soil temperature and moisture fluctuations during and after prescribed fire in mixed-oak forests, USA. Natural Areas Journal. 22(4): 296-304. 

Iverson, Louis R.; Dale, Martin E.; Scott, Charles T.; Prasad, Anantha. 1997. A GIS-derived integrated moisture index to predict forest composition and productivity of Ohio forests (U.S.A.)

Research Participants

Principal Investigators

• Louis Iverson, USDA Forest Service- Northern Research Station Research Landscape Ecologist
• Anantha Prasad, USDA Forest Service- Northern Research Station Ecologist
• Matthew Peters, USDA Forest Service- Northern Research Station GIS Analyst
• Stephen Matthews, Ohio State University Wildlife Landscape Ecologist  

Research Partners

• Todd Hutchinson, USDA Forest Service- Northern Research Station Research Ecologist
• Joanne Rebbeck, USDA Forest Service- Northern Research Station Plant Physiologist
• Daniel Yaussy, USDA Forest Service- Northern Research Station Supervisory Research Forester

For further details log on website :
http://www.nrs.fs.fed.us/sustaining_forests/conserve_enhance/timber/contrasting_silvicultural_systems/