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Burr Oak dropping leaves #648204

Asked 2020-06-09 14:22:01

1) Our nice burr oak is dropping leaves . Most are slightly eaten on edges . My guess is scale // ?? Can I spray â”- with what?? Thank you !! 2) sorry second question â” About 25 year old white pine is â˜'browning â˜' it's needles . I don't see any bugs/ rust ,,etc.. Anything I can do ??

Washington County Minnesota

Expert Response

Thank you for writing.
I am sorry the pictures are just not clear enough.
One possibility center picture is Oak Leaf Gall  https://hortnews.extension.iastate.edu/2010/8-25/oakgalls.html#:~:text=These%20growths%20are%20known%20as,by%20small%20wasps%20or%20midges.
Oak wilt is the worst case scenario.  https://extension.umn.edu/plant-diseases/oak-wilt-minnesota#how-is-the-oak-wilt-fungus-spread%3F-1258961

This pamphlet on Oak Diseases may give you a better idea.  http://www.myminnesotawoods.umn.edu/wp-content/uploads/2015/03/HowToRecognizeCommonDiseasesOaks.pdf 

In any case a large oak is valuable.  Consider calling a qualified arborist.  https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional
In the case of the pine, I need a close up of the needles and two small branching points. Blister rust would be the most common  https://extension.umn.edu/plant-diseases/white-pine-blister-rust  but Cytospora Canker, commonly thought of as a Colorado spruce disease also affects white pine.  https://extension.umn.edu/plant-diseases/cytospora-canker

Steve Miles Replied 2020-06-09 14:37:00
Thank you very much for your response ..  Sorry for  poor pics....  Tree is very healthy â” except for recent leaf issues ..  Took some ,,I hope ,, better photos..

not sure what is happening to the nice pine â”- bummer 

 Again, Thxs so much for your time and expertise ...
     Jack St. Ores 
     Baytown 
The Question Asker Replied 2020-06-09 14:44:18
Thank you very much for your response ..  Sorry for  poor pics....  Tree is very healthy â” except for recent leaf issues ..  Took some ,,I hope ,, better photos..

not sure what is happening to the nice pine â”- bummer 

 Again, Thxs so much for your time and expertise ...
     Jack St. Ores 
     Baytown 
The Question Asker Replied 2020-06-09 14:44:24
Fascinating.
The oak problem appears to be a twig gall--see those bumpy things at the twig just before it gets to the leaf.  http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/other/galls/gouty-horned-and-other-twig-galls.aspx

I can not find anything on management but the literature suggests the tree will survive.  I suggest you call an arborist per info given in my first post.
With regard to the pine--should a picture of the needles and twig branching from 6 inches away.  


Steve Miles Replied 2020-06-09 16:05:46
Steve,,
 thanks again...    In another life ,,was deep into biology â”- education / work .  So ,  find your support very helpful .. We live in a wonderful  area â” 8 acres ,, pond / small lake =   Almost a wildlife preserve . My wife is an officer in local Stillwater garden club â”-  they volunteer gardens in area ,, like by the hospital.
    I  understand some type or â˜'oil â˜' spay in the Fall helps with this gall â” will investigate ..Have 7  100+ year old white oaks I need to protect ....
      Be safe
The Question Asker Replied 2020-06-09 18:15:07
You as well.
It was peaceful out there today
Steve Miles Replied 2020-06-09 20:42:02

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