Fruitless Mulberry Tree Bark Damage

Canker

• Mulberry trees are susceptible to canker diseases like that caused by the Nectria fungus. A canker is a dark, depressed area appearing on the bark of the branch, twigs or trunk of the tree -- an open wound -- that contains dead tissue and is surrounded by a circle of callused tissue. In many instances, a dark resin will ooze from the canker. The tissue of the tree is often girdled -- strangled -- and the appendage may die.

Canker Management

• Fungal fruiting bodies also damage the bark of the tree and exist to spread their canker spores. In severe cases, the fruitless mulberry tree may be killed by the disease. Insuring the health of the tree can help to avoid an attack of canker, while dead and dying branches should be pruned away when the disease first appears. Unfortunately, once the trunk of the mulberry tree is infected, little can be done to save the specimen.

Heart & Sap Rot

• Several fungal diseases known as heart or sap rots initially attack the inner wood of the fruitless mulberry tree, rotting away limbs and branches. Bark damage is typically limited until the appearance of the fruiting fungus of the disease in the form of structures called brackets or conks. These jut out from the bark of the tree, looking like shelves attached to the trunk of the mulberry. Fleshy, mushroom-like fruiting bodies also appear attached to the bark or the earth at the base of the tree.

Wetwood

• Several types of bacteria produce the condition known as wetwood or slime flux on the bark of a fruitless mulberry and many other trees. Trees that are 10 years or older are most likely to exhibit symptoms produced by the bacteria in the form of large, stained spots on the bark that ooze a bacteria-filled fluid. Injuries to the bark and wood of a mulberry tree allow the bacteria to enter, so avoidance of those injuries is crucial in holding wetwood or slime flux at bay.