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Tanglehead (Heteropogon contortus), a native perennial C4 grass, historically was considered a decreaser throughout southern Texas. In the past ~ 20 years, tanglehead has increased dramatically, especially in the Texas Coastal Sand ecoregion; causative factors likely include a combination of changes in land use, climate and fire. Tanglehead can produce over 4000 kg ha-1 with foliar cover exceeding 100% and near-100% residual dry matter cover; adult plants are long-lived and seed production is prolific. When native vegetation is replaced by dense tanglehead monocultures, wildlife habitat is degraded and livestock grazing value is reduced. There is growing evidence that invasive grasses can affect ecosystem processes, including nutrient and energy exchange as well as soil microbial communities. Plant communities that are (i) dominated by tanglehead, (ii) a mixture of tanglehead and native species, or (iii) dominated by native species differ with respect to soil microbial biomass (carbon and nitrogen) and microbial community composition and structure; these differences, however, are temporally-dynamic. Prescribed fire in the spring can kill up to 60% of adult tanglehead plants but removal of residual dry matter allows for substantial seedling recruitment (> 1,500 seedlings m-2). Freshly-collected and 2-year old seeds have high viability (> 90%) and germination (> 80%). However, viability and germination of buried seeds decline to ~20% after years; thus, tanglehead does not form a persistent seedbank, and management practices that promote seed burial for at least 2 years may be effective. The combination of summer-prescribed fire followed by herbicide (Arsenal? or Spike?) can reduce adult tanglehead plant density for at least 2 years; single-treatment management practices (prescribed fire; herbicide; discing) are less ineffective.