The Comings and Goings of Trees

Post date: Jan 29, 2016 9:06:26 PM

On the tour, I had the opportunity to spend some time revisiting a couple of areas where we worked last May. While tanoaks and Douglas fir have been succumbing to the drought consistently over the prior three years of drought, I was shocked to see mortality in the normally robust redwoods over the past five months of drought.

At the first spot we had puzzled in May to find a young 100+’ redwood, its branches all intact, completely denuded even when it was still relatively moist. Redwoods do sometimes succumb to disease, but it usually follows damage to the to growing crown admitting disease organisms and this tree was perfectly conical all the way to the top. In October, two more nearby redwoods of similar size and stature, which had been thriving in May, were now bare as well.

The second spot was sadder still as there in the Lockheed Fire footprint the redwoods, again over 100’ tall, in May had shown the green pipe-cleaner look characteristic of having lost all their branches and needles in the fire and yet regenerated. This capability unique to redwoods.

While the first spot seemed to be a result of a disease spreading through the roots and hadn’t spurred regenerativecrown sprouting, the good news is that in the second spot the bottoms of the fire survivors that had died over the summer were densely ringed with healthy crown sprouts.

This fall has also been remarkable for the tanoaks, which are experiencing a rare mast year. A mast year, more typical in true oaks, occurs when a forest produces a superabundance of acorns (masts being the generic name for hard fruits). This has given the squirrels ample opportunity both to ballistically express their feelings about our working under their trees and to forgetfully plant many of those acorns. A further hopeful sign in the tanoaks is that we still have not encountered any in the San Vicente Redwoods with signs of Sudden Oak Death Syndrome, just drought stress and Armillaria Root Rot. Armillaria Root Rot, while just as fatal for tanoaks and very widespread in Bonny Doon, is not nearly so virulent in other tree species.