Disease on Sand Cherry

Question: The base of one branch of my sand cherry tree has a reddish gummy substance oozing from areas on the base of the branch. Can you identify the issue and describe a remedy? Shall we just remove the branch at the base?

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied June 15, 2023, 11:39 AM EDT
response: Oozing sap like this is termed "gummosis" and it can have several potential causes. Common among them is a wood-boring insect or an infection (fungal or bacterial), though sap oozing due to plant stress from environmental conditions is also possible. Our current drought is likely exacerbating things unless the plant is already being monitored for watering needs. Sand Cherries prefer cooler climates and here in the mid-Atlantic we are at the southern end of their heat hardiness, so chronic summer stress is a possibility.  Cherries tend to be vulnerable to an array of pests and diseases so it's hard to determine what the exact cause is here. (The linked page is focused on decorative flowering cherries, but fruiting species are essentially prone to the same problems. You can explore our cherry insects and cherry diseases pages for additional issues relevant to the fruiting forms.) When a wood-boring insect or infection sets in, often the original trigger was plant stress that weakened it and made it more vulnerable to infection/infestation, though occasionally healthy plants are invaded.  There is no treatment if an insect or pathogen is responsible for this damage. Since Sand Cherries tend to be multi-stemmed shrubs in our region as opposed to single-trunk trees, you can trim off this branch and let replacement branches regrow from the base of the plant over time. If you inspect the removed stem by splitting apart the wood you might find indications of which issue it was -- discolored "stained" wood, either in the interior or just under the bark near the gummosis, which would suggest an infection; tunneling and frass (insect poop, sawdust-like in this case) would be due to a borer, the larva of which would probably still be inside the wood somewhere. While it's possible this gummosis is due to neither issue and instead is merely stress, leaving the branch on the plant to see if the oozing stops risks spreading the pathogen further if that winds-up the culprit after all, so it's up to you how much of a risk you want to take. If the branch is too weakened or is dying at any point, the foliage at its end will wilt, dry out, or fall off and will not regrow.  Miri

responder: The Question Asker Replied June 15, 2023, 2:05 PM EDT
response: Thank you so much for your very informative response!On Thu, Jun 15, 2023 at 11:39 AM Ask Extension <<personal data hidden>> wrote:

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied June 15, 2023, 2:19 PM EDT
response: You're welcome!