Grass bud responses to fire in a semiarid savanna system

Increasingly, land managers have attempted to use extreme prescribed fire as a method address woody plant encroachment in savanna ecosystems. The effect that these fires on herbaceous vegetation is poorly understood. We experimentally examined immediate (<24 hr) bud response of two dominant graminoids, C3 caespitose grass, Nassella leucotricha, and C4 stoloniferous Hilaria belangeri, following varying energy (J/m2) semiarid the Edwards Plateau ecoregion Texas. Treatments included high- low-energy determined by contrasting fuel loading no burn (control) treatment. Belowground axillary buds were counted their activities classified determine effects activity, dormancy, mortality. High-energy burns resulted mortality N. leucotricha H. belangeri (p < .05). Active decreased high-energy for both species In contrast, remained constant control. treatment, 100% (n = 24) individuals resprouted while only 25% .0001) 3 weeks treatment application. Bud depths differed between may account this divergence, with average 1.3 cm deeper than .0001). Synthesis applications: Our results suggest directly affects activity through soil heating species. It imperative understand how impacts banks grasses better predict grass increased management.