Restoration of C-4 grasses with seasonal fires in a C-3/C-4 grassland invaded by Prosopis glandulosa, a fire-resistant shrub Academic Article uri icon

abstract

  • Questions: Can prescribed fire restore C4 perennial grasses in grassland ecosystems that have become dominated by fire-resistant C3 shrubs (Prosopis glandulosa) and C3 grasses? Do fires in different seasons alter the direction of change in grass composition? Location: Texas, USA. Methods: We quantified short- and long-term (12 yr post-fire) herbaceous functional group cover and diversity responses to replicated seasonal fire treatments: (1) repeated-winter fires (three in 5 yr), (2) repeated-summer fires (two in 3 yr), and (3) alternate-season fires (two winter and one summer in 4 yr), compared with a no-fire control. Results: Summer fires were more intense than winter fires, but all fire treatments temporarily decreased Prosopis and C3 annual grass cover. The alternate-season fire treatment caused a long-term increase in C4 mid-grass cover and functional group diversity. The repeated-summer fire treatment increased C4 short-grass cover but also caused a long-term increase in bare ground. The repeated winter fire treatment had no long-term effects on perennial grass cover. Mesquite post-fire regrowth had increasingly negative impacts on herbaceous cover in all fire treatments. Conclusions: Summer fire was necessary to shift herbaceous composition toward C4 mid-grasses. However, the repeated-summer fire treatment may have been too extreme and caused post-fire herbaceous composition to "over-shift" toward less productive C 4 short-grasses rather than C4 mid-grasses. This study provides some of the first long-term data showing a possible benefit of mixing seasonal fires (i.e., the alternate-season fire treatment) in a prescribed burning management plan to restore C4 mid-grass cover and enhance overall herbaceous diversity. 2010 International Association for Vegetation Science.

published proceedings

  • APPLIED VEGETATION SCIENCE

author list (cited authors)

  • Ansley, R. J., Boutton, T. W., Mirik, M., Castellano, M. J., & Kramp, B. A.

citation count

  • 18

complete list of authors

  • Ansley, R James||Boutton, Thomas W||Mirik, Mustafa||Castellano, Michael J||Kramp, Betty A

publication date

  • October 2010

publisher