Dead Trees in the Sierra Nevada

The last time we had been in Kings Canyon was two years ago.  We didn't see any recently dead trees then, but this year there were lots of them. I believe this is year 5 of the California drought.

Intensity:

• D0 (Abnormally Dry)
• D1 (Moderate Drought)

• D2 (Severe Drought)
• D3 (Extreme Drought)

• D4 (Exceptional Drought)

The dead trees, as you can see still have their leaves on them which means that they haven't been dead for long. In theory, these trees shouldn't be dead since they are growing right next to a river, but they are dead.  So maybe they died more of heat stress than of drought.  There is also the phenomenon of bark beetles which attack living trees which have been stressed by drought.  The bark beetles finish off the trees that haven't been completely killed by the drought.
These pictures were taken in a national park so the dead trees don't all get cut down, but outside the park and especially around people's houses, the cutting down of trees is mandatory since they pose a fire hazard.

 Here's a whole cluster of dead trees.

 And another.  It seems like overall, about 10 per cent of the trees at the bottom of the valley were dead. The dead trees are mostly Ponderosa pines since that is what there is most of but also cedars and sugar pines.

 The toll of dead trees seemed higher on south facing slopes and conversely lower on more shaded north facing slopes.

 This patch of forest was hit by fire at some point.  The dead trees here no longer have their needles and some regrowth in the understory has already started.

And another shot of an area where fire had gone through and deciduous shrubs and trees have filled in.
Hard to say how long the drought will last, but every year of no rain will mean more dead trees and large areas of the Sierra Nevada will be covered in dead trees and dead trees will be susceptible to fires.  The Sierra Nevada will move more toward a brown look from a green look, maybe like this part of the canyon where a fire moved through last year.

The look is lovely in a brown sort of way and it may be the way that the drought is pushing the Sierra Nevada. New trees are already coming up in burnt over areas but whether they can grow to maturity is a matter of whether the drought ends before all the trees have died.  Once all the trees in an area are dead they can only repopulate slowly by seeds brought in from outside the dead area and that only if climate conditions revert back to wetter conditions.