White Oak Survival

Which of these Oregon white oaks (Quercus garryana) from the Cove Fire site do you think will survive?

The Cove Fire consumed nearly 31,000 acres of the Modoc National Forest in July and August of 2017. Approximately six months after the fire was controlled, Leonard and I again checked the site (along Forest Road 40N11 near Adin CA) that we are monitoring to document the forest’s recovery.

Many of the Oregon white oaks were completely devoid of leaves, others had all their leaves intact, but those leaves were brown or scorched, while other trees had some branches with brown/scorched leaves and other branches without leaves. Of course, there were also white oaks that obviously were burned beyond possibility of survival.

We assumed that the white oak trees without leaves were heavily damaged, and those with scorched or brown leaves might survive. I snapped a few twigs of the trees devoid of leaves and found them to be green and supple. The twigs with brown leaves still clinging were dry and dead. Leonard and I began to search for buds on the trees and continued snapping twigs.

Buds

The trees without leaves had healthy buds on the twig ends while the trees with brown leaves had no visible buds. This was exactly the opposite of what we anticipated – the leafless trees, we assumed, had been badly burned but the trees with brown leaves still visible, we thought, were only scorched.

On earlier visits to the burn site we were focused on ponderosa pines and did not devote much attention to the white oaks. I remember oaks immediately after the fire with some green leaves and some brown leaves. But oak observations slipped through the cracks.

What I believe happened is that the branches or trees that were not damaged (green leaves remained) completed their fall cycle of normal leaf drop and became bare. Those trees or branches with scorched leaves, where the branches and twigs died, did not complete their usual leaf drop, so the leaves remained. The Oregon white oaks without leaves in January were the healthy trees that survived the Cove Fire, while those with brown leaves remaining on the twigs were dead.

Partial Leaf Scorch

I wonder if this tree with some bare branches and some branches bearing brown leaves will survive – and if it does survive, what the crown will look like once it greens out.

 

Gallery | This entry was posted in Trees and tagged , , , . Bookmark the permalink.

5 Responses to White Oak Survival

  1. Lin Erickson says:

    Very interesting !

  2. tonytomeo says:

    Many of the Western oaks will regenerate from the roots even after the tree dies. I am not familiar with the response of the Oregon white oak. The related valley oak does it, but those that regenerate from large trees are likely to succumb to decay of the large roots.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s