Black Walnut - bugs and rot

[Canyon Angler]

Hey, all, I'm hoping you can give me some advice.

I have a black walnut, about 23" DBH.

About 10 years ago (not long after buying the property) I removed a very big limb that stuck way out away from the main stem. Although I hated to cut it, I was afraid that it might break/split from its own weight, or that a storm/hurricane (we're near the coast) might one day take the limb down and split or otherwise destroy the tree in the process, so I figured removing it was good preventive maintenance.

I was careful to do an undercut (i.e., take out a face cut wedge underneath) before cutting from the top, and (I thought) I was careful to leave the branch collar intact so that the bark could close up around where the branch was. A couple years later, after the branch collar had started to close up around the top and sides (but not that much at the bottom) I sawed away some of the dead wood at the bottom of the branch to make it "easier" for the branch collar to close up. (Originally the stub of the removed limb stuck out much further at the bottom.)

Anyway, despite knowing better and trying to be careful, all I can conclude 10 years later is that I did cut off part of the branch collar

and now I have to deal with what I've got.

As you can see in the photos below, the stub of the limb is rotting, and bugs are eating/creating tunnels into the tree. Some of the bugs look like "sow bugs" and some of them look like slugs or snails without shells.

I have sprayed Sevin and Dursban and Malathion into the rotted wood and tunnels, but I'm not sure how well it's working, since the critters come back.

Can anyone recommend anything (besides hiring a tree surgeon) that might help this tree, kill the bugs and/or arrest the rot? Would borax/borates do any good? I don't want to lose the tree if possible.

Thanks in advance for any advice.

 

[treeseer]

yup you tore the cut while removing instead of reducing a branch. 2 bad moves there. :chainsawguy:

Now you are waging chemical Armageddon against innocent bugs while refusing to pay a penny on a pro.

If you had gangrene, would you spray it with roach poison, and refuse to call a doctor?

 

[rayIN]

Remove as much of the punky dead wood - to help it close over - while taking care not to touch live wood or bark. I can't give you advice on insecticides, other than I wouldn't bother.

Also I would ignore the posters making snarky remarks.

 

[treeseer]

ok snarkiness aside the tree is not responding too badly. yes scoop punky stuff but most importantly take care of the roots--recycle leaves, or mulch. aerate and fertilize per need, end some of the turfgrass competition, esp on that side of the tree.

And yes preferably call a tree surgeon who knows what they are doing.

 

[s37d]

One thing is for certain: there are no innocent bugs.

 

[ctrees4$]

keep in mind that no matter what you do to the tree it will have a weak spot where you made the cut and the rot will continue to travel down, I would suggest planting another tree and prepare to cut the walnut down in the future.

 

[Mike Van]

I can't see much of the tree in your pics, but would guying that limb back to the to the upper part of the tree been a better move than lopping it off?

 

[treeseer]

keep in mind that no matter what you do to the tree it will have a weak spot where you made the cut and the rot will continue to travel down.

Ever hear of compartmentalization, aka codit? y'see, this guy Shigo...

But you are right re a guying/cabling. Hindsight is so much better!
So are tree surgeons!

"One thing is for certain: there are no innocent bugs."

Falser words were never spoken. :help:

 

[Urban Forester]

"One thing is for certain: there are no innocent bugs."

Falser words were never spoken. :help:

Thanks "TS"... I was coming-a-running on that one!

 

[Canyon Angler]

But you are right re a guying/cabling. Hindsight is so much better!

I considered that for a year or so before removing the limb ... my (late) father's idea.

I should have listened to him.

Thank you all for the replies.

CA

P.S. As for planting replacements ... I do that every year! Lost a big 30" DBH mahan pecan a couple years ago, but I have about 10 of its offspring doing very well!

P.P.S. I recently bought two anti-fungals to spray on my apple trees...Captan and Immunox ... would either of them be appropriate to try to stop the fungal rot in the walnut?

Thanks again.

 

[Urban Forester]

P.P.S. I recently bought two anti-fungals to spray on my apple trees...Captan and Immunox ... would either of them be appropriate to try to stop the fungal rot in the walnut?
Thanks again.

No, foliar fungus is a different "breed" than rot fungus. Captan controls scab and other related foliar diseases as well as a few root fungi. Immunox is a DMI (demethylase inhibitor) fungicide labeled for about the same diseases. A word of caution, DMI fungicides should be used at max labeled rate to help reduce resistance from the targeted fungi. A respirator should be worn when mixing/spraying Captan.

 

[s37d]

Falser words were never spoken.

How do bugs help wood?

 

[treeseer]

How do bugs help wood?

Some insects eat other insects that eat living wood, for instance. Most are innocent bystanders.

One thing is for certain: there are few guilty bugs.

:biggrinbounce2: