Rock's Dragon Tree (Dracaena Rockii) is a species of Dracaenas that is is endemic to the Hawaiian islands Maui and MolokaŹ»i. It's habitat is restricted to remnants of lowland lowland dry, and sometimes open mesic or moist forest in gulches on Central Molokai and the northwestern flank of Haleakala; or on old lava flows on the southern flank of Haleakala, Makawao and Olinda on Maui. It grows at mid to low elevation (500 to 1,200 meters).
Rock's Dragon Tree is a tree that may reach five meters. The leaves are up to 40 centimeters long, bright green above, pale green below, tapering from near the base to the subulate tip. It can bear numerous fruit.
The first part of its scientific name, Dracaena, is a feminine form of the Greek word drakon and therefore means 'female dragon'. The second part, Rockii, honours the Austrian-American explorer, geographer, linguist and botanist Joseph Rock (1884 – 1962), who emigrated to the United States in 1905 and moved to Honolulu, Hawaii in 1907, where he eventually became an authority on the flora there.
The species is threatened by habitat loss. There are probably fewer than 5,000 or 10,000 individuals remaining in an undetermined number of occurrences. It is in some places still fairly common. However, due to the array of threats to this species, regeneration is very poor and most of the remaining individuals are mature trees. Threats to the species include feral pigs, goats, deer, rats, invasive alien plants, grazing, and fire. The tree also suffers from limited dispersal, with almost all fruits falling directly under the parent canopy, poor dispersal can contribute to increased seed predation levels by introduced rodents.
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