| Water resource surveys in Big Bend National Park have been conducted periodically and with varying intensities to detect long-term trends in hydrology and vegetation. In 1995, 40% of 331 water sources supported tamarisk ( Tamarix spp.). A time-intensive, park-wide effort to remove tamarisk from springs began in 1998. The study objectives were to determine the methods necessary to record the plant community where tamarisk is consistently removed, track the establishment and re-growth of tamarisk, and determine the effectiveness of current removal methods over several years. Based on vegetation sampling literature and spring site visits, 5 transects and 18 to 40 quadrats at each spring were read. No significant difference in plant cover was recorded from 2000 to 2002. No re-growth of tamarisk was observed. The removal methods were effective for at least 2 years. The Tamarisk Monitoring Handbook for Desert Springs was developed from the study. |
