ABSTRACT
Conservation and preservation concerns have led to efforts to understand mechanisms of invasiveness and the effects these mechanisms have on the environment. Vitex rotundifolia L. f. [beach vitex (BV)] was introduced as a salt-tolerant woody ground cover, but it has since become invasive on primary and secondary dunes in coastal areas of the southeastern United States. Much of its invasive potential may be the result of intense substrate hydrophobicity underneath established stands, which is believed to prohibit seedling establishment by other plants including native plant species. This research was conducted to better understand BV-induced sand hydrophobicity by carrying out dune surveys of BV-infested areas of the South Carolina coast, identifying the compounds responsible for this activity via chemical analysis, and quantifying hydrophobicity persistence by resampling sites following removal of above-ground BV. The findings indicated that sand under BV cover was significantly hydrophobic, that cuticular alkanes from leaves and fruits were responsible for this hydrophobicity, and that extreme substrate hydrophobicity persisted for >3 years following BV removal.
