Sick Oaks

[BillyB]

Hi,

I cut down a couple of oaks in my yard recently due to illness. One white and one red.

The white one (first 3 photos below) was alive but struggling. After dropping it, it became apparent hat it has a white fungus beneath the bark in one spot and on the outside of the bark as well.

The red one (photos 4-9 below) died last summer. Best guess at cause of death while it remained standing was 2 lined chestnut borer.

My plan was to stack the white one for firewood and burn the red one before the insects emerge this spring. My concern is that now seeing the trees up close, that I don't store a contagious disease on my property by storing the white oak or destroy a good amount of good firewood fuel by burning the red.

What are your thoughts? Ok to stack the white oak? Ought I destroy the red oak real soon?

I'm in Minnesota, zone 4 by the way.

 

[Jed1124]

Probably oak wilt fungus. The scenario is correct. Kills reds fast, whites take a bit of time.
Two lined chestnut borer is usually a secondary pest. I wouldn’t worry about it emerging.

 

[BillyB]

White Oak

• Could that fungus on the white oak be anything other than wilt? Do you think it still poses a threat to my woodland? Do I need to burn the wood asap or ok to stack for later?
• I'm not seeing visible signs lower down the trunk. Would that mean it likely hadn't infected the roots or its neighbors yet?

Red Oak
This was close enough to the white that the roots could touch. (There are others close by as well but I don't yet see any signs of disease on them.) This was the tree I was concerned about last summer because it died. However, it retained it leaves, though they were brown. My understanding is that wilt causes a tree to drop its leaves. Also, I bored a few sections of trunk for testing in the lab. Small branches would have been better but I couldn't reach any. The trunk sections came back negative for wilt but showed borer signs.