Proper Burning Intervals for Tobosagrass in West Texas Based on Nitrogen Dynamics

Abstract

The time required for re-establishment of pre-fire nitrogen levels in tobosagrass (Hilaria mutica) communities in the Rolling Plains of West Texas was studied on five different ages of burns over a 2-year period. Time elapsed after burns varied from one to five growing seasons for both convex and concave topographic sites near Colorado City, Texas. Standing old growth-N returned to pre-fire levels by the end of the third growing season. However, litter-N on the soil surface took 5 years to reach pre-fire levels on concave sites and an estimated 8 years on convex sites. High variation prevented the recognition of any meaningful trends in root or soil nitrogen levels. Based on this data, tobosagrass should not be burned more frequently than 5 to 8 years, depending on the site.