Wednesday, June 10, 2015


Spring came early after our non-winter. So far, 2015 is California's warmest year on record, and the Sierra has one of its weakest snowpacks. Light storms over the past two months have left recent snow at the Sierra crest, have kept the Merced from bottoming out, and have delayed the blue-skies-til-October summertime that we expect for Yosemite Valley and below.
In the past two weeks I've enjoyed being rained on, snowed on and hailed on. These storms are not overcoming general drought effects, however: the Merced is flowing at about 1/5th of average volume and dead ponderosas greet visitors ascending from the foothills.

While you may read simplistic headlines that beetles are killing trees, they can only do this because the trees are weakened by drought and in some cases had been further stressed by a history of fire suppression. Preventing periodic ground fires allows too many trees to mature, each challenged by competition with too many neighbors. Regular low-intensity fires thin out young trees so that survivors are stronger and more resilient to drought and therefore to beetles.

On top of a precipitation deficit, warmer temperatures and an increased proportion of dead trees, these intermittent moderate storms have grown more light fuels - the kind that dry quickly and burn fast. Indications for an active fire season are worrying. For the moment, the wildflowers are still nice up and down the Merced corridor: globe gilia, LOTS of Clarkia, blazing star, tarweed, Datura, etc. Buckeyes are fading. There are still a few bright dogwoods in their highest, shadiest locales (Tuolumne Grove, Chinquapin).

Looking further ahead, strong El Nino conditions are shaping up in the Pacific and though there's no guarantee, we may have a wet winter coming.