Oak wilt risks & precautions - NE Ohio

[semifnordic]

I'm in a western suburb of Cleveland, OH, and the internet says oak wilt is all over the state. I've got several large oaks, mostly red oak. Unfortunately, despite being otherwise healthy, one of them is starting to crack in half and likely needs to be removed. Since it's next to the road and over powerlines, I called a reputable local arborist with a crane to take a look and quote removal. They also looked at and made recommendations on several of my other trees, including pruning several other oaks (described as "raise low hanging branches, thin interior sucker growth, remove dead wood over 3", and remove lowest main branch over house") No mention of oak wilt was made, I came across it on my own, and that led me to a few questions:

- It seems that it's strongly advised to avoid any pruning of oaks in spring and summer, let alone removing lower branches -- So, it seems I'd be best off waiting until after October to do any maintenance pruning on the other trees, right?

- My understanding is that the risk with pruning is the fresh sap attracting the beetles that spread oak wilt. I was hoping to save the wood & chips from the one that will be removed -- but now I'm wondering if cut wood or a pile of chips will also attract the beetles, and if that could lead them to my other healthy trees. Is there a risk to having a pile of freshly cut oak, or a pile of oak chips, on the property within 100' of other oak trees? Is there a way to mitigate this risk (ie I plan to seal the ends of larger pieces with Anchorseal, is that sufficient?)

- I had considered not grinding the stump, because the tree is close to other trees and I don't want to damage their roots, but will a fresh stump also attract beetles and be a risk to adjacent trees? Is grinding a large stump that's maybe 10' from another large tree likely to cause problems for the other tree?

 

[Tom Dunlap]

You're on a good track. Find out what current and local advice is. Contact your city forester.

One universal is the NO PRUNE in the spring. Without more information I'm concerned with the guy you contacted about removal and pruning. There should have been a discussion about the timing of pruning.

 

[evo]

Turns out Oak Wilt is on our doorstep. Going to be taking a crash course on oak wilt.
EAB is 2 hours north and south, so double whammy.
Are all oaks equally susceptible?

 

[KTSmith]

Evo, susceptibility does vary and/or the time before symptom expression. Red oak are most susceptible as a group, white oak is less susceptible as a group, and bur oak are intermediate. A good treatment out of the midwest is linked here: https://www.dnr.state.mn.us/treecare/forest_health/oakwilt/index.html . No, it's not very nice.

 

[Rusticus]

I'm in a western suburb of Cleveland, OH, and the internet says oak wilt is all over the state. I've got several large oaks, mostly red oak. Unfortunately, despite being otherwise healthy, one of them is starting to crack in half and likely needs to be removed. Since it's next to the road and over powerlines, I called a reputable local arborist with a crane to take a look and quote removal. They also looked at and made recommendations on several of my other trees, including pruning several other oaks (described as "raise low hanging branches, thin interior sucker growth, remove dead wood over 3", and remove lowest main branch over house") No mention of oak wilt was made, I came across it on my own, and that led me to a few questions:

- It seems that it's strongly advised to avoid any pruning of oaks in spring and summer, let alone removing lower branches -- So, it seems I'd be best off waiting until after October to do any maintenance pruning on the other trees, right?

- My understanding is that the risk with pruning is the fresh sap attracting the beetles that spread oak wilt. I was hoping to save the wood & chips from the one that will be removed -- but now I'm wondering if cut wood or a pile of chips will also attract the beetles, and if that could lead them to my other healthy trees. Is there a risk to having a pile of freshly cut oak, or a pile of oak chips, on the property within 100' of other oak trees? Is there a way to mitigate this risk (ie I plan to seal the ends of larger pieces with Anchorseal, is that sufficient?)

- I had considered not grinding the stump, because the tree is close to other trees and I don't want to damage their roots, but will a fresh stump also attract beetles and be a risk to adjacent trees? Is grinding a large stump that's maybe 10' from another large tree likely to cause problems for the other tree?

The pruning windows are very regional, but remember there are no always or nevers with nature. I see infections outside of our windows often. The best mitigation is to prune within the windows and paint all oak pruning cuts year round. It stops the smell from attracting the beetles and makes a physical barrier as well. Try to paint within minutes. After 3 or 4 days, the tree has already started compartmentalize it enough that painting is moot. I use cheap paint; there's no healing properties of pruning seal, anything will get where you want to be regarding paint.

The issue with storing logs on your property is if the tree died of oak wilt and now the logs are stored with the fungal mat that attracts the nitidulid beetles to spread to other trees' fresh cuts. If these trees died of other causes, there is no risk of that happening because wood chips and freshly cut logs won't be sustainable to be infected with oak wilt without an active vascular system.

The beetles can travel over 20 miles. Having piles of chips ans logs isn't a increased risk, in my opinion. It wouldn't hurt to cover it with some plastic for a couple months to put your mind at ease though.

Remember to paint the stump too, if you leave it. It wouldn't attract more beetles over grinding it. I can't comment on the distance grinding question...there's a few variables in there.

I also feel oak species will vary in tolerance of oak wilt, but not necessarily susceptibility.

 

[evo]

Well I feel like an idiot. We do have an Oak Wilt but a different animal than the stuff y’all are dealing with.
The bug is Mediterranean oak borer carrying Raffaelea montetyi
It will be interesting when the two overlap in range.

 

[semifnordic]

Thanks everyone!

You're on a good track. Find out what current and local advice is. Contact your city forester.

One universal is the NO PRUNE in the spring. Without more information I'm concerned with the guy you contacted about removal and pruning. There should have been a discussion about the timing of pruning.

The forestry manager in my city didn't have much to say but reiterated the wait until fall / winter advice for pruning, so that does seem pretty universal, and I'm wondering why it wasn't mentioned by the company I talked to -- they're one of the few that's actually owned by an arborist, and isn't just "Joe's Tree Removal Etc." I suppose in my area most people don't think much about trees until they want them gone.

A neighboring city appears to have a more robust urban forestry department, with three arborists on staff and a citywide tree survey etc. One of their people responded to me with several resources on oak wilt & also recommended pursuing preventative treatment for my other trees, which I need to do more research on.

The issue with storing logs on your property is if the tree died of oak wilt and now the logs are stored with the fungal mat that attracts the nitidulid beetles to spread to other trees' fresh cuts. If these trees died of other causes, there is no risk of that happening because wood chips and freshly cut logs won't be sustainable to be infected with oak wilt without an active vascular system.

Thanks, this is exactly what I wasn't able to find information on. All the readily available information online was about trees that had already been killed by wilt -- in my case, the tree appears healthy, it's just got a crack forming that looks like it's going to split in half and fall on the road & powerlines.

 

[Tom Dunlap]

Those two pictures tell a story

Without some cabling/bracing/crown reduction failure is likely.

At a minimum installing some temporary ropes to support the two sides is important. Every tree company has ropes that are too short for rigging but still have life in them. Loop around and tie bowlines. You could use a truckers hitch to tighten the temporary cabling.

No pruning now

Re visit in the fall with a permanent solution

 

[Rusticus]

Well I feel like an idiot. We do have an Oak Wilt but a different animal than the stuff y’all are dealing with.
The bug is Mediterranean oak borer carrying Raffaelea montetyi
It will be interesting when the two overlap in range.

That's one I need to learn more about. "Interesting" indeed.

 

[semifnordic]

@Tom Dunlap with the winning suggestion here. I had another company (Bartlett, they actually sent an arborist instead of the removal crew lead) take a look at that tree today. They're proposing 5 brace rods through the cracked junction, a cable up higher (he indicated galvanized steel cable, through-bolted; said dynamic rope-based cable systems aren't as good), preventative oak wilt treatment (presumably propiconazole), and revisit for pruning in the fall.

I suppose this is getting a bit off-topic, but does anyone have opinions on how long-term a cable / brace fix for a red oak is? Am I more likely to be buying it a long happy life, or buying a couple years before an expensive removal where the wood now has a bunch of metal bits in it?