In fact, ultraviolet irradiation is actually detrimental as it inhibits photosynthesis, photoreduction, and the 520 nm light-dark absorbance change of algae.
Additionally, adult "halli" typically appear pale-eyed, while adult "giganteus" of the normal morph typically appear dark-eyed (occasionally flecked paler).
It has been heavily exploited for its strong, dark red, resinous wood, which is useful for the construction of buildings, bridges, boats, and telephone poles.