Begins on the lee side of oceanfront dunes, shell mounds and coastal berms and extends as far inland as suitable conditions allow. Soils are neutral to moderately alkaline and consist of sand and shell fragments, although porous limestone dominates in the Florida Keys. Fertility is good due to surface litter and humus accumulation; drainage and moisture retention is fair. Plants tolerate moderate amounts of salt, shading and drought, with those native to the Keys the most drought resistant. They require reasonable soil fertility and drainage, and will do well farther inland where preferences are met. Tropical plants dominate in warmer areas, temperate species in colder zones. Some plants listed as understory trees and shrubs function as canopy in the coppice forest closest to the coast.