Blue Oaks 2013—Summer Hibernation?

July 7, 2013

The Blue Oaks have shut-down dramatically in the past few days, apparently letting their leaves go to conserve moisture. We’ve had ten straight days of 100+ degrees, nothing abnormal for July. But last season we received less than 10 inches of rain, or 57% of the average of the seven years prior. Only once last season did we receive over an inch of rain in a 24-hour period on December 4, 2012. We’ve had no deep moisture.

I’ve seen this happen before after extended periods of excessive heat, more like 30 days straight over 100 degrees. But I don’t recall it happening so early in the summer, nor to such a large percentage of trees, what appears to be about 50% so far.

Most of these Blue Oaks are 100 years old, but there are a few grandfather trees that may be 200 or 300 years old. One has to assume that they are not only rooted in the right place, but that they have survived worse years than this.

I’ve misplaced my “Life of an Oak”, an informative book, and found nothing on the Internet about this phenomenon that is probably shared by many species of trees. We will monitor as we go forward.