When cherry trees fail to leaf out in spring, it's probably time to start over.
Cherry trees die from many causes but young trees die most often, failing because of drought or injury soon after transplanting. Older cherry trees suffer from insect attack and fungal disease, especially when growing in difficult situations. Stress due to poor soil or insufficient water makes trees more susceptible to other types of damage. Often only parts of the tree die, and even major damage sometimes heals with proper pruning. Diseased or neglected trees sometimes take years to totally succumb. Does this Spark an idea?
Instructions
1. Look for healthy leaves in spring, summer and early fall. Look for leaves that bend without breaking and show a glossy green color. Dry and brittle leaves throughout the canopy during the growing season definitely indicate problems, if not death.
2. Expect a normal leaf fall in autumn. Leaves on dying trees shrivel and turn brown, and often remain on the tree for months.
3. Test twigs in late winter after the worst of the cold passes. Bend twigs to check for dead brittle wood. Dead twigs snap easily, but even in winter live twigs will flex without damage.
4. Inspect bark in late winter. On twigs and small branches where bark normally grows with a smooth surface, dead bark blisters and cracks. Winter damage often affects only the most tender growth, so dead twigs don't indicate a dead tree. When patches of dead bark completely girdle a branch, the branch can't be saved. Prune out all dead or diseased wood, according to North Dakota State University.
5. Check the bark of major branches and the main trunk by pricking slightly with a knife. Rough hard outer bark should cover a layer of bright green cambium. A layer of brown dry fiber over the sapwood means that critical cambium layer died.
6. Find the graft junction between rootstock and grafted cultivar. In grafted varieties the junction shows as a swollen area on the lower trunk. If the tree above the junction shows no sign of life but shows healthy bark below the junction, the rootstock might still recover and send up sucker shoots in the spring. Careful pruning might provide a healthy base for a new graft. Mahaleb and Mazzard rootstocks often produce suckers, according to Virginia Tech.
Tags: cambium layer, dead bark, junction shows, late winter