Sooty Bark Disease

Question: My neighbor had a maple tree (silver) trim by a tree expert and said the tree also has sooty bark disease. It had a lot of dead limbs but still has enough limbs to provide shade for a city lot. tree approx. 40' high.  Will the tree survive, or would it be best to remove and replace with another tree?

responder: Thank you for your question!   Laura S.      Michigan State University Extension Advanced Master Gardener Volunteer You may also contact the toll free MSU Extension lawn and garden hotline at 1-888-678-3464 with your gardening questions or visit www.migarden.msu.edu for Smart Gardening resources. Replied June 11, 2023, 2:00 PM EDT
response: Hello James, Would you please attach a picture taken far enough back to show the whole tree so we can see he dieback in the crown? Also tell us, is there any sticky sap evident beneath the tree, such as on cars, or patio furniture beneath the tree? Are the fallen leaves or twigs sticky or sooty?

responder: The Question Asker Replied June 12, 2023, 9:39 AM EDT
response: Is there any sticky sap evident beneath the tree, such as on cars, or patio furniture beneath the tree?  ANSWER:  No sap at all.  Just the some black stuff as seen on the attached pictures at the base of the tree and on a higher limb junction about 15 feet off the ground.Are the fallen leaves or twigs sticky or sooty?  ANSWER:  The leaves are not sticky.  There are many just dried up and crumpled leaves from multiple sides of the tree.  Some of the leaves have many black blotches (see picture).Thank you for your help On Sun, Jun 11, 2023 at 2:00 PM Ask Extension <<personal data hidden>> wrote:

responder: Thank you for your question!   Laura S.      Michigan State University Extension Advanced Master Gardener Volunteer You may also contact the toll free MSU Extension lawn and garden hotline at 1-888-678-3464 with your gardening questions or visit www.migarden.msu.edu for Smart Gardening resources. Replied June 12, 2023, 10:05 AM EDT
response: Thank you for the additional pictures and information. No sticky sap is good news, since that would indicate an insect( aphids or scale) present.   The dark spots on leaves and the falling of these leaves is a wide spread condition found this year in Michigan, anthracnose and/or maple leaf blister.  https://www.canr.msu.edu/news/maple_leaf_blister_and_anthracnose_two_foliar_diseases_that_can_appear_on_s  There is no treatment, and the tree will recover. Just be sure to water the tree the equivalent of 1 inch of water per week while we are in drought conditions. This will help the tree push out new leaves from dormant buds and will reduce the stress on the tree from the lack of rainfall.  To properly water a tree, thoroughly soak the entire area under the branches of the tree. Apply one or two inches of water twice a week when no rain is expected. If you use a sprinkler, you can place a flat-bottomed baking dish in the area being watered and watch the level to determine when 1 to 2" of water has been applied. More details on watering established trees is here: https://extension.umn.edu/planting-and-growing-guides/watering-established-trees-and-shrubs#when-to-water-trees-and-shrubs-1261760  The blackened areas didn’t come out clearly in the pictures. I am referring this to our MSU Forestry expert for his opinion.

responder: The Question Asker Replied June 12, 2023, 10:20 AM EDT
response: Thank you for the explanation. You been very helpful. On Mon, Jun 12, 2023 at 10:05 AM Ask Extension <<personal data hidden>> wrote:

responder: Thank you for contacting Ask Extension!  Replied June 12, 2023, 1:53 PM EDT
response: I will comment on the "dark mold tree crotch" photo. The photo of the base of the trunk is too low resolution to view. A crotch such as this results in what is essentially two competing trunks. Both "trunks" continue to expand in girth, causing them to grow into each other at the base (the "crotch"). This results in an inherent weakness at that position in the tree, and creates an entry point for both insects and disease. Preventative pruning many years ago would have best. At this point, it is a weakened section that should be evaluated by a certified arborist, given that it is in a residential setting. It may be fine for years, or it may split in a heavy storm. To find a certified arborist to look at your trees: https://www.treesaregood.org/