Oak wilt problem

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treesquirrel

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I am currently removing a large 40 DBH red oak from a customers front yard that I am certain is a victim of Oak wilt. While I have been there I have identified two other smaller red oaks with symptoms. they have asked me to go ahead and remove those as well. I plan to see if I can pinpoint some spore mats and confirm the diagnosis, maybe take a sample to the local forestry office.

This worries me because this customer lives in a gorgeous wooded area with an abundance of red and white oaks. This tree was so well grown and spectacular it is sickening to have to remove it.

I don't think this property owner has the funds to move forward with effective control measures so I would welcome any suggestions from any of you guys/gals with disease expertise.
 
Alot of times in our area twolined chestnut borer damage and oak wilt are confused and misdiagnosed...leading to the removal of trees that otherwise could be saved. Also Anthracnose, and oakwilt are also confused. However, if you are sure of the oakwilt diagnosis, there is little you can do other than isolating the infected trees and sanitizing the healthy ones from the infection, ie trenching, and treating healthy trees.
 
Alot of times in our area twolined chestnut borer damage and oak wilt are confused and misdiagnosed...leading to the removal of trees that otherwise could be saved. Also Anthracnose, and oakwilt are also confused. However, if you are sure of the oakwilt diagnosis, there is little you can do other than isolating the infected trees and sanitizing the healthy ones from the infection, ie trenching, and treating healthy trees.

Yes, the death timeline for this tree was what leaned me towards oak wilt. Also the pattern of discoloration of the leaves. There are a few places where bleeding is present that I will peel bark back and get a sample from. I expect to find a spore mat.
 
Oak Wilt is harder to field diagnose in Red Oaks than in Live Oaks. If you can find a Red Oak that died a while back, and you can find the fungal mats that smell like Juicy Fruit gum, you've got Oak Wilt. Bacterial Leaf Scorch (BLS) looks very similar in Red Oaks. Your best bet is to send samples of twigs and leaves off to your state's diagnostic center.
 
Good luck to you, and your client. Oak wilt has been devastating in our area, and we have lost a lot of trees. Kind of suprised by your post...did not know it had been a problem in Southern US also.
 
Good luck to you, and your client. Oak wilt has been devastating in our area, and we have lost a lot of trees. Kind of suprised by your post...did not know it had been a problem in Southern US also.

Thanks, this is a case where I hope to be wrong but looks like I am right. A bad deal for everyone down here.
 
Oak Wilt is harder to field diagnose in Red Oaks than in Live Oaks. If you can find a Red Oak that died a while back, and you can find the fungal mats that smell like Juicy Fruit gum, you've got Oak Wilt. Bacterial Leaf Scorch (BLS) looks very similar in Red Oaks. Your best bet is to send samples of twigs and leaves off to your state's diagnostic center.

Thanks! I will check for the odor as well. The bleeding should produce this correct?
 
Alot of times in our area twolined chestnut borer damage and oak wilt are confused and misdiagnosed...leading to the removal of trees that otherwise could be saved. Also Anthracnose, and oakwilt are also confused. However, if you are sure of the oakwilt diagnosis, there is little you can do other than isolating the infected trees and sanitizing the healthy ones from the infection, ie trenching, and treating healthy trees.

yes, make sure to cut the roots leading to any other trees BEFORE cutting down the infected tree.
 
Thanks! I will check for the odor as well. The bleeding should produce this correct?

I've never seen bleeding in Oak Wilt. The fungal mats that form under the bark in Red Oaks, manifest as dark, raised patches that slightly lift up the overlaying bark. By peeling back the bark and sampling the odor, you can discern the Juicy Fruit smell. While the patches sometimes look a bit shiny, they are mostly non-weeping, from my experience. Weeping may give evidence of a secondary infective agent being present.
 
Good luck to you, and your client. Oak wilt has been devastating in our area, and we have lost a lot of trees. Kind of suprised by your post...did not know it had been a problem in Southern US also.

Oak Wilt has been a huge problem in the South for many, many years. Dr. David Appel, at Tx. A&M, is one of the foremost researchers in the field, and a world authority on Oak Wilt. Austin, TX., my home town for over thirty years, was one of the first Oak Wilt centers studied. In some areas, here, 95% of Live Oaks and Red Oaks have been killed. It is eerie to see the giant Live Oaks dead yet still standing for years at a time. I believe that most Red and Live Oaks, here, will be wiped out over the next fifty years until that time that naturally resistant trees triumph over the disease and spread, once again.
 
Sunrise, I can remember reading somewhere that it had started in the southern US. but I guess I have been kinda wrapped up in the local problems here, and it just had slipped my mind. Too quick to post..too slow to think...too old to remember...pick an excuse, or accept an apology.
 
Sunrise, I can remember reading somewhere that it had started in the southern US. but I guess I have been kinda wrapped up in the local problems here, and it just had slipped my mind. Too quick to post..too slow to think...too old to remember...pick an excuse, or accept an apology.

Apology? Nah, none needed. We all have our local issues. It's tough to keep up on all diseases, all the time, in all the trees, in all the states. It also seems that every time you turn around, some new disease is coming down the pipe/pike. Throw in diseases that will off us, like the new super bacteria recently found, and who can keep it all together?
 
Yeah, with EAB here in MN now, ALB on the rise, and we are still dealing with DED, and OW, plus now we are looking for Thousand canker of Walnut, and several others. Its hard to keep up, just with the threats here. I sometimes do not think through what I post however. For this ...I thank you for your understanding.
 
I'm sure you have a lot of large cottonwoods in decline from "poplar decline complex".

That's funny JP. We definately don't need that one.

Back to the Oak Wilt. If the OP can get a twig sample with the leaves that have recently died but is still not totally dead and is still supple enough to bend without breaking he can slit and peel the bark on the twig. If the cambium has a black or very dark brown streaking as it is called under the bark it is definately Oak Wilt. In cross section it will appear as a black, dark brown circle under the bark on the sample. Typical clogging of the vascular system of the tree from the fungi that cause DED, Vert. and Oak Wilt.

July and August are the prime months for these wilt diseases to take a tree out in a very short time. All it takes is some hot humid weather, throw in some dry conditions due to lack of rainfall. Next thing you know you have a dead tree in as little as two to three weeks.

We have a subdivision here that Oak Wilt just went wild after the houses were built in a undisturbed natural wooded area. The trees that came down with the Oak Wilt were the weak ones. These trees that died usually had some kind of problem such as decay in the stem or in the root collar. Cutting roots during the construction phase didn't help either.

It has been many years since we have worked in that area. I don't know if it is because of more competion for tree removal work or the disease has just run it's course in the area and is not killing too many trees.
 
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