Wild black cherry sap - Ask Extension
Why are some of our wild black cherry trees oozing an abnormal amount of sap from the trunk?
Knowledgebase
Wild black cherry sap #853393
Asked October 18, 2023, 8:13 AM EDT
Why are some of our wild black cherry trees oozing an abnormal amount of sap from the trunk?
Clare County Michigan
Expert Response
Good Morning,
Gum and bleeding is a result of a break in the bark of the tree and, there are a lot of different things that can break through the bark. The injury can be due to freeze damage (in this case the sap shows up in the early summer), or from insects or mechanical damage.
There are three groups of organisms that can cause cankers on cherries and result in a gummosis response.
· One is a bacteria in the genus Pseudomonas which causes a disease known as bacterial canker.
· Another is a fungus in the genus Leucostoma (Cytospora) that causes Leucostoma canker of Prunus.
· The third is usually called fungal gummosis and is caused by the fungus Botryosphaeria dothidea.
It is not important in a practical sense to identify the specific organisms involved but, it is important from a diagnostic point of view to differentiate between insect infestation, mechanical injury, and infectious disease. In all three of the diseases listed above, the key diagnostic feature is the canker.
A canker is a necrotic (dead), often sunken lesion on a stem, branch, or twig of a plant. In the case of gum bleeding from the trunk of a cherry tree, a canker can be identified by the death of tissue immediately beneath and surrounding the point of gummosis. If you carefully scrape away the gum and probe the bark beneath, you will find the bark loose and the tissue beneath discolored. In fact, the bark at the point of gummosis may slough off easily indicating dead tissue. Clean the gum away with a sterile knife but do not dig too deeply, then treat with a copper fungicide, available at most lawn and garden stores. Read and follow label instructions.
You may find these website of interest: http://www.walterreeves.com/landscaping/bleeding-cherry-tree-gum-on-bark/
http://aces.nmsu.edu/ces/yard/2001/101301.html
Sticky Situations on Cherry Trees | Horticulture and Home Pest News (iastate.edu)
Gummosis of Fruit Trees (missouribotanicalgarden.org)
Ornamental Cherry Trees: Identify and Manage Problems | University of Maryland Extension (umd.edu)
I hope this helps. Thanks for using our service.
Gum and bleeding is a result of a break in the bark of the tree and, there are a lot of different things that can break through the bark. The injury can be due to freeze damage (in this case the sap shows up in the early summer), or from insects or mechanical damage.
There are three groups of organisms that can cause cankers on cherries and result in a gummosis response.
· One is a bacteria in the genus Pseudomonas which causes a disease known as bacterial canker.
· Another is a fungus in the genus Leucostoma (Cytospora) that causes Leucostoma canker of Prunus.
· The third is usually called fungal gummosis and is caused by the fungus Botryosphaeria dothidea.
It is not important in a practical sense to identify the specific organisms involved but, it is important from a diagnostic point of view to differentiate between insect infestation, mechanical injury, and infectious disease. In all three of the diseases listed above, the key diagnostic feature is the canker.
A canker is a necrotic (dead), often sunken lesion on a stem, branch, or twig of a plant. In the case of gum bleeding from the trunk of a cherry tree, a canker can be identified by the death of tissue immediately beneath and surrounding the point of gummosis. If you carefully scrape away the gum and probe the bark beneath, you will find the bark loose and the tissue beneath discolored. In fact, the bark at the point of gummosis may slough off easily indicating dead tissue. Clean the gum away with a sterile knife but do not dig too deeply, then treat with a copper fungicide, available at most lawn and garden stores. Read and follow label instructions.
You may find these website of interest: http://www.walterreeves.com/landscaping/bleeding-cherry-tree-gum-on-bark/
http://aces.nmsu.edu/ces/yard/2001/101301.html
Sticky Situations on Cherry Trees | Horticulture and Home Pest News (iastate.edu)
Gummosis of Fruit Trees (missouribotanicalgarden.org)
Ornamental Cherry Trees: Identify and Manage Problems | University of Maryland Extension (umd.edu)
I hope this helps. Thanks for using our service.
