Thuja Green Giant - Browning - Ask Extension
I have 3 Green Giants approximately 7' tall. This spring we noticed the trees are starting to turn brown. I assume it is some type of fungus. Is there...
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Thuja Green Giant - Browning #628653
Asked April 28, 2020, 5:38 PM EDT
I have 3 Green Giants approximately 7' tall. This spring we noticed the trees are starting to turn brown. I assume it is some type of fungus. Is there a fungicide that can be sprayed to cure this? Pruning seems like a daunting task as it would remove much of tree branches. Attached are the photos. Your recommendations would be greatly appreciated!
Oldham County Kentucky
Expert Response
It looks like winter freeze discoloration and not a disease.
I don't know how long they have been planted in your landscape but if it is a new planting the root system would have not fully recovered and not been able to keep enough moisture in the branches and you might also have some wind burn damage.
I recommend not trimming them. They they should recover fine.
Applying a copper fungicide will protect them from diseases.
Contact the Oldham County Extension Service Office for additional information.
http://oldham.ca.uky.edu/
I don't know how long they have been planted in your landscape but if it is a new planting the root system would have not fully recovered and not been able to keep enough moisture in the branches and you might also have some wind burn damage.
I recommend not trimming them. They they should recover fine.
Applying a copper fungicide will protect them from diseases.
Contact the Oldham County Extension Service Office for additional information.
http://oldham.ca.uky.edu/
Thanks for the response Michael. They have been planted for almost 2 years. I was concerned since there was an ashy gray color visible on the branch’s in between healthy growth. Is that nothing to be concerned about?
It can take up to 5 years for the roots to recover for a tree the size you planted.
The gray color in between the healthy growth are possibly areas that have been physically damaged in some way. It does not have characteristics of a disease problem. The gray color on the bark is normal as the bark matures. New twig growth will start green and mature to a grayish brown as the branch grows.
Contact the Oldham County Office for publication on disease control options.
http://oldham.ca.uky.edu/
The gray color in between the healthy growth are possibly areas that have been physically damaged in some way. It does not have characteristics of a disease problem. The gray color on the bark is normal as the bark matures. New twig growth will start green and mature to a grayish brown as the branch grows.
Contact the Oldham County Office for publication on disease control options.
http://oldham.ca.uky.edu/
