Giant sequoia trees
have a natural defense against forest fires thanks to thick, fire-resistant bark at the lower part of their trunks. However, encroaching vegetation, typically fir trees, can act as a fire ladder bringing the flames of a fire to the sequoias canopy where the natural defenses are less effective. These encroaching trees all compete with the sequoias for essential ground water.
In 2011, on a private lot in central California, a small
preservation project was started. An ancient sequoia tree was being shadowed and crowded by tall fir trees. After climbing and inspecting the crown of the giant sequoia, it was observed that the fir tree was growing through the giant sequoia and causing die back and damage to the giant sequoia. It was also observed that, if a forest fire were to happen, the large firs would enable the flames to reach the canopy of the sequoias where they are most vulnerable.