The status of U.S. Virgin Islands' forests, 2004
Forest covers 21 237 ha of the U.S. Virgin Islands, 61 percent of the total land area. St. John had the highest percentage of forest cover (92 percent), followed by St. Thomas (74 percent), and St. Croix (50 percent). Forest cover has decreased 7 percent from 1994 to 2004, a loss of 1671 ha of forest. Most notably, St. Croix lost 986 ha (11 percent) of subtropical dry forest and St. Thomas lost 307 ha (13 percent) of subtropical dry forest. The forest of the U.S. Virgin Islands consists of very young, undeveloped stands, reflecting past and present land use and disturbances. Eighty percent of the forest inventoried was in stands mostly made up of saplings and seedlings (d.b.h. < 12.5 cm). The remaining 20 percent of the forest was dominated by stands composed of small diameter (12.5- to 22.4-cm d.b.h.) trees.The inventory sampled 105 tree species, 47 species as trees with d.b.h. ≥ 12.5 cm. Sixty species were found only as saplings or seedlings. Among the species present as trees with d.b.h. ≥ 12.5 cm, black mampoo [Guapira fragrans (Dum.-Cours.) Little]) had the highest importance value, followed by gumbo limbo [Bursera simaruba (L.) Sarg.]) and genip (Melicoccus bijugatus Jacq.). Ninety-five tree species were found as saplings or seedlings (d.b.h. ≤ 12.4 cm), and of these, tan tan [Leucaena leucocephala (Lam.) de Wit)] had the highest important value.There were few indications of stressed trees or widespread pest and disease problems. Only 3.8 percent of live trees had some type of damage or disease. Amounts of down woody material (DWM), forest floor duff, and forest floor litter increased as the forest environment became more humid, but overall the U.S. Virgin Islands’ forests lack large pieces of DWM on the forest floor, perhaps because they are in an early successional stage and have few large trees.