Rapid Geographic Spread of the Alien Orchid Eulophia GRAMINEA IN FLORIDA

摘要

Eulophia graminea is a terrestrial orchid native to Asia that was found to be naturalized in Miami-Dade County, Florida in 2007, and by 2008 was known from five locations in that County. The public, through a newspaper story, orchid club members, native plant club members, and field botanists in southern Florida were requested to assist in detecting new locations of the orchid in order to monitor its spread. In addition, the author searched for the orchid in woodchip mulch habitats in the region. Readers of a Miami Herald newspaper story, Fort Lauderdale orchid club members, and field botanist colleagues detected the most occurrences of the orchid. By the fall of 2010, E. graminea had been detected in 67 sites in 7 counties in southeastern and southwestern Florida, occurring within a 16,000 km~2 area. While most of the occurrences were in landscapes at residential, educational and commercial locations, 16 occurrences were in parks and preserves, and four of these were in undisturbed native vegetation. Woodchip mulch remains the most common substrate in which the orchid grows, but the exact role that mulch plays in facilitating the growth and/or spread of the orchid is unknown.