Historical versus contemporary medicinal plant uses in the US Virgin Islands

Hidden in the documents of the dark past of the trans-Atlantic slavery are gems of ethnomedicinal observations, supported by herbarium specimens, which tell of the traditional medicine of a by-gone slave society in the Caribbean. In the context of the former Danish West Indies (now US Virgin Islands), we identify pre-1900 medicinal plants and their historical uses, and trace their status in the traditional medicine of St. Croix today (2014). By a combined historical and ethnobotanical approach we assess the scale of loss and preservation of traditional medicinal knowledge on St. Croix, and explore the drivers involved in the disappearance of knowledge in the oral tradition of medicine.

Names, uses and identities of 18th and 19th century medicinal plant uses in the Danish West Indies were derived from manuscripts and publications of Von Rohr (1757/58), Oldendorp (1777), West (1793), Benzon (1822), Riise (1853), Eggers (1876;1879) and Berg and Eggers (1888). The presence of the plant species in the pre-1900 Danish West Indies was confirmed by review of herbarium specimens in the University of Copenhagen Herbarium (C). The same species were collected on St. Croix in 2014 or their ecological status discussed with local specialists. Semi-structured interviews supported by photographs and specimens were conducted with six medicinal plant specialist on St. Croix, to document and compare contemporary names and uses of the historically used medicinal plants.

The historic ethnomedicinal sources revealed 102 medicinal uses of 64 plant species. Thirty-eight (37%) of the pre-1900 medicinal uses were traced in interviews, while sixty-four uses (63%) appear to be forgotten, discontinued or otherwise lost. Thirteen species appear to have entirely lost their status as medicinal plants on St. Croix, while 32 species (50%) have lost uses while retaining or gaining others. While 20% of the lost medicinal plant uses can be explained by biodiversity loss, and others likely have become obsolete due to advances in public health and scientific medicine, 33 of the 64 lost medicinal uses of non-rare species uses fall in the same categories as the preserved uses (fever, stomach, wound, laxative, pulmonary, intestinal, pain, anthelmintic, blood purifier, eye-inflammation). We therefore argue that at least half of the known pre-1900 medicinal plant uses have become culturally extinct for other reasons than to biodiversity loss or modern obsoleteness.

The present study utilized knowledge from an oral medicinal tradition, documented in the context of a colonial society. Without doubt, basis for further similar studies exists in the more or less accessible archives, herbaria and collections of former colonial powers. Such studies could directly benefit the descendants of the original intellectual property holders culturally and economically, or serve as stepping stones to integrate, or re-integrate, lost medicinal plant uses in both local and wider evidence-based contexts.