Your tree has Canker disease. It is caused by environmental stress (poor watering habits, freeze damage), mechanical injury (ramming it repeatedly with your lawn mower or the weed whacker), or disease and insect infestation. It is either a bacterial infection or a fungal infection but that doesn't really matter. To control it, use all your dormant sprays (especially copper) on schedule (Thanksgiving, Christmas and Valentine's Day). Prune only when the tree is in active growth (late spring, early summer). If it is a fruiting cherry, the perfect time is when you are picking. Use a funicide on all your pruning cuts and sterilize your tools between cuts with bleach or alchol (I use alcohol, bleach is hard on metal). Don't let anything grow up to the trunk of your tree. You can clean out the cankers by scraping out the goop and dead wood and spraying with copper sulfate or another fungicide. |
It looks like gummosis. |