Hi there we have received a white oak from the Toronto tree program.It is located in our west facing garden below a huge maple tree. However I have noted peeling bark recently. I tried to spray it with soap and water as there was one white foamy area on the main tree . Is there any thing else I should do apart from adequate water and ? fertilizing the tree. I cannot remove that old sugar maple
Thanks for your question.
A foamy area on a white oak can be indicative of bacterial wetwood, also known as bacterial slime or slime flux, a common disease that affects the central core of many shade and forest trees, including white oak. In many situations, affected trees do not suffer permanent damage. However, if your tree is under stress from other factors such as soil compaction, this bacteria can cause yellowing and wilting leaves and branch dieback. Siting the white oak under a mature sugar maple may be a stress factor as it competes for soil nutrients and water.
Our recommendation is have an arborist take a look at your white oak, or, if it is recently planted, to get back in touch with the Toronto tree program from which you received it. Landscape Ontario offers a list of Toronto and area arborists on their website, here.