The coastal tall-grass prairie, which extends along the coastal plain of South-central Texas and southwestern Louisiana, represents the southernmost extension of the tall-grass prairie ecosystem. Once covering at least 9 million acres, today more than 99% of this important habitat has been lost to agricultural range improvement and urbanization. The remainder is highly fragmented and severely threatened by exotic species and development. The coastal tall-grass prairie ecosystem is currently listed as "imperiled globally" by The Nature Conservancy and the Texas Natural Heritage Program. The World Wildlife Fund lists the conservation status as "critical" (Ricketts 1999).
Armand Bayou Nature Center preserves one of the most extensive holdings of coastal tall-grass prairie in the lower Galveston Bay watershed. Currently, 645 acres are actively managed, about 70% of the long-range goal of 900 acres within our current boundaries. All of the prairies at ABNC have been altered to some degree, initially by cattle grazing and agriculture. The greatest impact however has been the result of the recent expansion of the Chinese tallow tree (Sapium sebiferum), which can grow into a closed canopy forest and severely limit native prairie plant diversity. Significant restoration activities at ABNC have begun to reduce the acreage impacted by this invasive species and has also led to an increase in management activities to maintain their condition.
The single most important tool in ABNC's prairie restoration arsenal is the use of a controlled, prescribed fire. We conducted our first prescribed fire in 1978. Fire is perhaps the most dramatic and least understood element of prairie ecology. In historical times, lightning or Native Americans ignited prairie fires. It is believed that the native people used fire to drive game, improve pastures for game and clear migration routes. Prairie ecosystems thus evolved with fire as a necessary component of their ecology.
Prairie plants are well adapted to fire. They have evolved unique growth habits to protect their delicate tissues from the intense heat. The budding cells are located at or below ground level where they escape the high temperatures and experience little damage from the fire while some prairie plants actually require fire in order to grow.
Fire has a number of associated benefits to the prairie. It removes dead plant material and thatch that has accumulated in previous growing seasons and returns it to the soil in the form of ash. This recycling of nutrients and the rapidly warming blackened soils following a prairie fire contribute to a healthy prairie. The single most important benefit of fire in the prairie landscape is the suppression of brush and other woody plant species. Trees such as the non-native Chinese tallow tree and shrubs are not well adapted to fire and are suppressed or often killed in the process of a burn. In the absence of fire, prairies are slowly degraded by the invasion of trees, shrubs and other woody species. Over time, trees will create a closed canopy harvesting most of the available sunlight. This lack of sunlight causes the shading out the original native prairie plant community.
Recognizing the historical importance of fire in the prairie landscape, Armand Bayou Nature Center uses fire as a tool to restore and maintain the health of our prairies. Prescribed burning is the use of fire to achieve a specific ecological goal in the prairie landscape. Our prescribed burn team consists of staff and trained volunteers. Go to the Volunteering web page for information about becoming a burn team member.