Unhealthy Cherry Trees
Greetings, I have a Northstar Cherry that was planted this spring. It's about 5 ft. tall. (It was a pricey gift from my brother and why I don't want to give up on it.) It started out beautiful and lush but doesn't look good now. I see two main issues: brown spots on leaves and a soft, gummy build up of something at a joint. Earlier this spring, it had a build-up of sap in the same location, then it seemed to disappear and now it has a golden, spongy mass. I'm wondering if I have two issues to contend - canker and leaf spot. ?? Additional considerations: - I have many voles in the garden, and their holes continue to show up near the base of the tree (I plan to trap & relocate them.) - I have deer (maybe only one as evidenced by hoof prints) that continue to visit the tree and eat it's leaves. (apparently, they love the taste as they have mostly left other other plants alone.) I've used deer repellent which seemed to help but with it's fast growth this spring, it was hard to keep up on the application. - I have another cherry tree 15-20 feet away that I purchased from a box-store. It's about 3-4 years old. Last year, it had spots on the leaves and suffered from ill-health, visiting deer and voles. (I was hoping this year would be different but it wasn't the case. It has never bloomed for me. Maybe it's a male?) I've included pictures of this as well b/c they may be suffering from the same issue/s. If I should remove this tree, I'm OK with that. There's no sentimental value. Would you please help me diagnose and recommend treatment? I'm happy to provide more photos, do FaceTime, or have a call to help identify the problems. Sincerely, Corina **This is a side note that you may ignore if you don't have time or expertise in this area. I live in the center of downtown GR on Highland Park. (https://www.grandrapidsmi.gov/Directory/Places/Parks/Highland-Park) The last couple of years, I've noticed deer visiting - 2-3 adults and 1-2 fawns. I'm surprised at their audacity to frequent our sometimes busy park and eat plants right next to the house. I have dogs that bark at them when they're noticed. I'm growing a native garden that isn't fenced in. (next to the cheery trees) If I do a better job protecting my cherry trees with the natural spray I've been using, is it possible that they will decide my homely garden isn't worth the visit or will they continue to visit anyway? Is my best hope to have a garden in this spot, to fence it in?
Kent County Michigan
Nice Job with the pictures! Lets start with the deer. If they are used to living around people they will feed on the plants. You probably have neighbors who feed them as well. A fence is the most effect way to protect your plants.
Both cherry trees have cherry leaf spot. This is a hard disease to control unless you spray fungicides frequently https://www.canr.msu.edu/ipm/diseases/cherry_leaf_spot
The NorthStar cherry also has gummous where the plant exudes sap and gum at the site of a would. This could be either an insect or a disease. The most likely disease is bacterial canker. https://www.canr.msu.edu/ipm/diseases/bacterial_canker_blossom_blast#gallery
It could also be an insect such as lesser peach tree borer https://www.canr.msu.edu/ipm/diseases/lesser_peachtree_borer or American plum borer https://www.canr.msu.edu/ipm/diseases/american_plum_borer, both of which attack the shoots of cherry trees. You can remove the spongy gum. Ohio State has developed a good resource on home fruit tree care.
Ohio State has a good book on home fruit tree care. It is available from many states for free as a PDF. Here is one from Kentucky. https://plantpathology.ca.uky.edu/files/mw_home_fruit_productn_b591.pdf
Purdue also has a good resource for pest control for the home gardener for both tree fruit, grapes, strawberries and raspberries. https://www.extension.purdue.edu/extmedia/ID/ID-146-W.pdf
Finally, Your unknown cherry tree is a sweet cherry. Sweet cherries bloom on 2 year old wood and a slow to begin blooming. It looks like you are pruning the tree pretty hard, cutting off most of the new growth (or are you just cleaning up what the deer leave behind). I would suggest only cutting off the tips of the branches or removing whole branches rather than cutting off most of the new growth.
Sweet cherries require a pollinizer another different variety to cross pollenate the flowers and to set fruit. Here is more information https://ask.extension.org/questions/648250