There are many more
dead and dying trees in the park this
year than in past years. One of the
main causes is an outbreak of the fir
engraver bark beetle (Scolytus
ventralis), which attacks white firs.
The outbreak is caused by stressed
white fir trees, which have suffered
from several years of drought.
The beetles burrow under the bark
and kill a strip of cambium near its
gallery to successfully reproduce.
The fir engraver beetle infestation
may result in a few dead branches, a
top kill, or complete tree mortality.
Although the dead trees may not be
aesthetically pleasing, fir engraver
beetles are a natural part of
ecosystem processes. They are
further evidence of how difficult it is
to survive in the harsh Great Basin
climate, where water is a limiting
factor for most species.
