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ABSTRACT <br />Boa 63 Pur 586 <br />Spoil islands constructed during dredging of the Intracoastal ' <br />Waterway and other navigable channels constitute a significant man-made <br />habitat type in east -central Florida, and offer unique opportunities for <br />upland habitat enhancement. To study the feasibility of native <br />vegetation establishment on these islands, nineteen native species and <br />one ornamental exotic species were planted on an upland portion of a <br />Spoil island in the Indian River near Vero Beach. Seedlings from 2 -inch <br />liners were planted beneath the Australian pine (Casuarina <br />equisetifolia) canopy, with no soil preparation, or subsequent <br />fertilization or watering. <br />After 19 months, species survival rates ranged from 100% for pigeon <br />plum (Coccoloba diversifolia) and Spanish stopper (Eugenia foetida) to <br />27% for scaevola (Scaevola frutescens) and West Indies mahogany <br />(Swietenia maha oni). Net survival was 74% (221 of 300 seedlings <br />planted). Extremely high tides during a severe fall storm inundated <br />portions of the planting area (37 seedlings) and buried 79 seedlings <br />beneath vegetative debris, dramatically increasing seedling mortality in <br />the affected areas. All species exhibited substantial growth ranging <br />from 74% (West Indies mahogany) to 933% (wild lime, Zanthoxylum fagar•a). <br />Disturbance of the Australian pine litter and soil surface <br />facilitated invasion by Brazilian pepper (Schinus terebinthifolius), <br />which soon dominated an adjunct live oak acorn (Quercus virginiana) <br />planting site. Preservation of an intact soil and litter layer, and <br />retention of at least a moderate canopy of Australian pines appeared <br />vital to successful vegetative restoration on these spoil islands. <br />Commissioner Lyons asked if the types of seedlings planted <br />would provide food for birds, and Mr. Fernald stated they <br />specifically used tropical species because they do provide some <br />high qualify fruit for birds. In a larger project, they would <br />hope to include some more temperate species that also would <br />provide fruit. <br />18 <br />