Cherry tree diagnosis
Cumberland County Pennsylvania
Thank you for your question. I believe what your tree is experiencing is called White Flux. The following information comes from Texas A&M University Extension; I hope it helps you to understand what's going on with your tree.
Finding white frothy fluid oozing from the trunk of your prized landscape tree can be alarming. Don't panic; the good news is that the disease responsible for this unsightly condition is largely preventable with proper cultural care.
White flux, also known as foamy canker or alcoholic flux, occurs when bacteria penetrate bark wounds or cracks and the underlying cambial tissue. The multiplying organisms ferment the sap, releasing alcohol and gasses. Pressure from the gasses builds inside the tree, eventually forcing white frothy liquid through the cracked bark. The froth has a slightly yeasty odor.
The fluid temporarily bleeding from a tree during warm weather is the external symptom of more serious internal damage. Left unchecked, white-flux bacteria rot the cambial layer, limiting the tree's wound-healing ability.
Prevention and Control
To reduce a tree’s risk of white flux, avoid wounding it when you mow or trim weeds and keep it adequately watered during dry, hot weather. Gauge when to water by inserting a tile spade -- available from a garden supply center -- into the soil near the tree. Scoop out a soil sample. If the entire sample feels dry or slightly moist, water the tree. If only its top is wet, increase watering time so moisture reaches the lower roots. To control a minor infection, cut out the wounded, frothing area and let it heal. To relieve internal pressure that may aid in recovery, drill a small hole (one-half inch diameter or less) directly below the bleeding site and slightly upward into the center of the trunk. Install a tight fitting drainpipe in the drilled hole making sure the end of pipe extends far enough outward so that sap does not fall on the tree. Removal is the only option for trees with severe white flux.