There is an interesting Hawaiian legend tied to the Ohia tree and its flower, the Lehua blossom. The legend is tied to the volcano goddess, Pele. This story explains that if you pluck this flower, it will rain on the same day (for a tragic reason).
The legend of the Ohia tree and the Lehua blossom
The legend says that one day Pele met a handsome warrior named Ohia and she asked him to marry her. Ohia, however, had already pledged his love to Lehua. Pele was furious when Ohia turned down her marriage proposal, so she turned Ohia into a twisted tree.
Lehua was heartbroken, of course. The gods took pity on Lehua and decided it was an injustice to have Ohia and Lehua separated. They thus turned Lehua into a flower on the Ohia tree so that the two lovers would be forever joined together.
So remember, Hawaiian folklore says that if you pluck this flower you are separating the lovers, and that day it will rain.
(read a longer version of the story here)