| Insects have always been a natural part of
the forest but we have seen them on a larger scale
in the past three years because of drought. Drought
puts stress on trees and stressed trees are more
susceptible to bark beetles. Other factors to
stressed trees are dense stands, construction
disturbance and even over watering.
In the summer time (June-August), bark beetles
fly and seek out live green trees to bore into.
They over winter in these trees and their eggs
develop into beetles and emerge the next summer,
starting the process all over again. These trees
are called ‘Brood Trees’.
The population of the Pinon Ips beetle
(Ips confuses) has increased in the valley. Ips
is a common group of bark beetles that infests
pine and spruce trees. Other varieties of bark
beetles are infesting and killing trees as well.
| Mountain Pine Beetle
– Saguache County was listed as one
of the areas with high MPB activity in the
state. Although MPB is leveling out in Ponderosa
Pine, there has been an increase of activity
in Bristlecone Pine. |
 |
Douglas Fir beetle continues
to advance at mid elevations. We are seeing activity
on the eastern San Juan mountains and western
Sangre De Cristo Mountain ranges.
The Fir Engraver beetle continues
to advance in both the western Sangre De Cristo’s
and eastern San Juan’s in White Fir and
Subalpine Fir. Unlike the the Pinon and Ponderosa
timber stands, the spruce/fir remains overstocked
and unhealthy.
 |
Spruce beetle
activity has advanced all around the SLV and
is of great concern due to the beetles’
rate of spread Roughly 2,000 acres on the
Rio Grande National Forest in Conejos County
has an estimated mortality of 100%. Salvage
treatments are underway. |
Thinning and preventive spraying continues to
be the principal tool for prevention and control
of the bark beetles.
For more information, please visit CSFS's "What's
Wrong with My Tree?" web page.
Alamosa
District Main Page |
