Lichens on koa branches are
common at elevations of 3500 feet or more on the Big Island of Hawaii. The
lichens are not believed to be parasitic or to cause any major plant health
problems, but according to some foresters may be an indication of declining koa
plant health. Others believe that lichens
are not necessarily indicative of declining trees. Heavy coverage can be so
because of the increased light reaching the boughs but there are many trees
that carry large colonies from early stages. The shrubby lichen that we
illustrate is Usnea hawaiiense
(probably a synonym of U. australis) and the foliose species is Rimelia reticulata.
Back
to Acacia koa