Description and map of the plant communities of the northeast coastal spray zone of Kalaupapa National Historical Park

Abstract

Two lichens, two ferns, and 66 flowering plants are recorded from the northeast coastal spray zone of Kalaupapa National Historical Park. Forty-four species (63%) are alien (introduced since 1778). Fourteen species have been declared noxious by the State of Hawai'i. Five species pose a potential threat to archaeological sites. One grass constitutes a fire hazard. Five plant communities are distinguished and mapped within the northeast spray zone on the basis of species composition and substrate: 1) a native-dominated community on sandy strand directly in the salt spray, 2) a half-native community on flat basalt with clayey soil above sea cliffs in the most intense salt spray, 3) a native community on rocky strand slightly protected from salt spray, 4) a small area of native-dominated prostrate shrubs on raised basalt domes, and 5) an alien-dominated grassland less influenced by spray. In addition, an alien scrub community borders the spray zone. A total of 25 localized plant associations are distinguished within the five spray zone communities. Management recommendations are for experimental exclosures to gauge the impact of feral herbivores, and for experimental salt water applications to control alien plants. The ecological diversity and intact nature of this native coastal vegetation argue for its sound management.