Firetree (myrica Faya) Distribution in Hawai`i

The primary objective of this study was to map the distribution and abundance of firetree (Myrica faya) in the state of Hawai`i. Reconnaissance data were used to map 85,912 a (34,365 ha) of infestation throughout the State. Infestations of 72,265 a (28,906 ha) occur on the island of Hawai`i, 4,770 a (1,908 ha) on Maui, 2,518 a (1,007 ha) on Lana`i, 435 a (174 ha) on O`ahu, and 5,925 a (2,370 ha) on Kaua`i. Distribution ranges in elevation from as low as 1,400 ft (425 m) on Lana`i to as high as 6,400 ft (1,940 m) on the slopes of Haleakala on Maui. Firetree occurs on recent, thin ash over pahoehoe lava as well as on deep, well-developed silty clay loam soil. It is found in montane rain forest habitats and in dry scrub (marginal through submontane seasonal) forest. The distribution patterns of firetree suggest that this species has not yet reached the limits of its potential distribution in Hawai`i. Observations on the phenology of firetree were made at two-week intervals from March 1983 through March 1985. Data were taken at three sites and were related to the data from nearby weather stations. Information on flowering, fruiting (mature and immature), leaf flushing, leaf fall, and fruit drop was collected. Analysis of the phenologic patterns observed showed flowering, fruiting, and fruit drop to be endogenously controlled, while leaf flushing and leaf fall were influenced by environmental variables.