Most remote sensing studies of species diversity have been based on the use of passive imagery representing the horizontal dimensions of ecosystems. However, LIDAR (light detection and ranging), provides a means to accurately quantify vertical structure. The goal of this study was to evaluate vascular plant species richness on a coastal barrier island using indicators of community vertical structure derived from airborne, multiple-return LIDAR data. Returns from a 3 m buffer area surrounding each of 90, 15 m vegetation line transects were extracted from LIDAR data of Horn Island, Mississippi, acquired in April, 2004. LIDAR indices did not correlate with richness when data for all habitats were combined. When habitats were considered separately, several LIDAR indices correlated significantly (p ⩽ 0.05) with richness in marsh, meadow and woodland habitats. Best-fit indices indicated the importance of vegetation height and structural complexity in estimating plant species richness.