RED OAK DIE BACK & DEATH - Ask Extension
Over the last ten years we have had three of our four lovely, mature Red Oaks die for no apparent reason. Lower limbs go first. (In the spring no le...
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RED OAK DIE BACK & DEATH #866848
Asked May 03, 2024, 7:33 AM EDT
Over the last ten years we have had three of our four lovely, mature Red Oaks die for no apparent reason. Lower limbs go first. (In the spring no leaves.) Our fifth and most magnificent continues to lose lower limbs, a few every year. What can we do to save it? Clay soil. Plenty of water. Soil line below root splay.
Frederick County Maryland
Expert Response
For the last several years we have been hearing many concerns about mature oaks declining. Scientists have been studying the issue and there is not one 'smoking gun' so to speak, but more likely a combination of stress factors involved, including more unpredictable weather due to climate change. 2018 was one of the wettest years on record and some mature trees literally drowned in standing water, while last year large parts of Maryland struggled with prolonged drought conditions.
Here is information on what is generally known as
'Oak Decline':
https://www.nps.gov/articles/oak-decline.htm
and
https://extension.umd.edu/resource/why-oak-trees-are-declining-or-dying/arec.umd.edu/resource/why-oak-trees-are-declining-or-dying
We'd suggest keeping the tree as stress-free as possible by expanding the mulched area widely around the tree so that there is less competition from your turf for water and nutrients. Mulch will also keep the roots cooler and more moist. Here is our mulching info- be sure to keep it no deeper than about 3" and pulled back from the trunk.
Here is mulching page:
You should also keep it irrigated when we don't get at least an inch or two of rain per week. A slow, deep drink is better than more frequent, shallow watering.
Here is our Watering Trees and Shrubs page:
https://extension.umd.edu/resource/watering-trees-and-shrubs/
This page can help you to evaluate how far the stress has affected the tree:
https://extension.umd.edu/resource/how-do-you-decide-when-remove-tree/
If the tree is important to you we suggest having a tree health expert, a.k.a. an ISA-certified arborist come and do an on-site evaluation of all the factors, and make recommendations. Most larger tree companies have them on staff but you can search for one at the credentialing agency as well at http://www.treesaregood.org
Christine
Here is information on what is generally known as
'Oak Decline':
https://www.nps.gov/articles/oak-decline.htm
and
https://extension.umd.edu/resource/why-oak-trees-are-declining-or-dying/arec.umd.edu/resource/why-oak-trees-are-declining-or-dying
We'd suggest keeping the tree as stress-free as possible by expanding the mulched area widely around the tree so that there is less competition from your turf for water and nutrients. Mulch will also keep the roots cooler and more moist. Here is our mulching info- be sure to keep it no deeper than about 3" and pulled back from the trunk.
Here is mulching page:
You should also keep it irrigated when we don't get at least an inch or two of rain per week. A slow, deep drink is better than more frequent, shallow watering.
Here is our Watering Trees and Shrubs page:
https://extension.umd.edu/resource/watering-trees-and-shrubs/
This page can help you to evaluate how far the stress has affected the tree:
https://extension.umd.edu/resource/how-do-you-decide-when-remove-tree/
If the tree is important to you we suggest having a tree health expert, a.k.a. an ISA-certified arborist come and do an on-site evaluation of all the factors, and make recommendations. Most larger tree companies have them on staff but you can search for one at the credentialing agency as well at http://www.treesaregood.org
Christine
This was very helpful. And free! Thank you.
You're welcome! Anytime.
