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About Our Herbaria Network
The US Virgin Islands Herbaria Network supports the enhancement of research cyberinfrastructure within US Virgin Islands for implementing shared specimen data hosting of plant specimens.

About the Virgin Islands
The U.S. Virgin Islands, an unincorporated territory of the United States, are made up of St. Croix, St. John, St. Thomas and numerous smaller islands centered on the geographic coordinates of 18° 20’ N by 64° 50’ W. With Puerto Rico to the west and the British Virgin Islands to the east and north, the U.S. Virgin Islands lie at the eastern extreme of the Greater Antilles. Puerto Rico, St. Thomas St. John and the British Virgin Islands are all part of the Puerto Rico Bank, a area of relatively shallow water, and were connected until rising sea levels at the end of the last ice age separated the islands about 8,000 years ago (Wiley and Vilella 1998, Rankin 2002). The much deeper waters of the Virgin Islands Basin, in places greater than 2,500 m deep, may have always kept St. Croix separate from her sister islands to the north (Wiley and Vilella 1998, Rankin 2002).

St. Croix is the largest of the U.S. Virgin Islands with a total area of 219 km2 (34 km long by 9.6 km wide). Its highest point, Mount Eagle, is 355 meters. St. John, the smallest of the three main islands, has a total area of 53 km2 (roughly 13 km wide), and its highest point is Bordeaux Mountain at 392 m. St. Thomas is 90 km2 (19 km long by 5 km wide), and its highest point, the highest in the U.S. Virgin Islands, is Crown Mountain at 474 m. The combined total area of these islands is roughly twice the size of Washington, D.C. (Central Intelligence Agency 2002).

Even though the U.S. Virgin Islands lie south of the Tropic of Cancer the cooling effect of the Atlantic Ocean to the north and Caribbean Sea and easterly trade winds throughout the year produce a subtropical climate with temperatures that average 25º C in winter and 28º C in the summer (Ewel and Whitmore 1973, Wiley and Vilella 1998). The U.S. Virgin Islands are generally drier than the rest of the Greater Antilles due to their lower elevations, averaging 1400 mm of annual rainfall mostly occurring in the months of July through October (Wiley and Vilella 1998). The overall lower elevations on the islands cause less orographic cooling, the process by which air cools as it is forced up the sides of mountains. As moisture-laden trade winds are forced up mountainsides, water vapor condenses, clouds form, and rainfall can result. Summer and early fall is hurricane season. Hurricanes are an important factor in the formation and dynamics of forests on many Caribbean islands (Weaver 1994, 1998b, a).