EFFECTS OF BURNS CONDUCTED IN SUMMER AND WINTER ON VEGETATION OF MATAGORDA ISLAND, TEXAS

We conducted prescribed fires on Matagorda Island, Calhoun County, Texas, in late summers (August) and early winters (January) of 1992-1993 and 1993-1994 to determine responses of vegetation and litter. There were reduced litter loads I year after burning, but they approached pre-burn levels 2 years after burning. There was no difference in production of grasses, forbs, or the juncus and other-Cyperaceae complex I year after burning. There was a significant difference in production of juncos and other Cyperaceae when years were compared. We presume this was caused by differences in precipitation between years. There was no difference in percentage frequency between burned and control plots 1 year after burning for most species examined. However, burning in summer significantly increased occurrences of coastal mistflower (Conoclinium betonicifolium), Fabaceae, and Cyperaceae (other than juncus) over control plots 1 year after treatment. Beach groundcherry (Physalis cinerascens) and Fabaceae also were increased by burning in summer 2 years following treatment. Prescribed burning did not affect density of vertical structure. Because coastal barrier islands serve as important wintering grounds and stopovers for many migratory birds, we recommend conducting burns in late summer every 2-5 years to increase incidence of legumes and other forage for wildlife.