Red Trunk Crab Apple Tree Disease

Crab apple trees often suffer from fire blight and powdery mildew.

Red jade crab apple trees are members of the Rosaceae family and have reddish-brown bark. According to the University of Florida IFAS Extension, red jade crab apple trees are susceptible to diseases that target the tree.

Types

Red jade crab apple trees can develop scab infections, fire blight, cedar apple rust, powdery mildew and certain canker diseases. Some crab apple cultivars are disease resistant, such as the jewelberry, Margaret and David.

Symptoms

Apple scab include dark spots on leaves, yellowing of leaves, fruit lesions and leaf drop. Fire blight symptoms include blighted branch tips, brown branch tips, drooping branches and scorched leaves. Severe fire blight kills many crab apples. Powdery mildew affects many ornamental plants, shrubs and fruit trees, producing a white fungus that coats the leaves. Red jade crab apple trees suffering from cedar rust develop rusty brown leaf spots and defoliation.

Control

Fungicides are often effective for fungal diseases. Some diseases, such as fire blight, have no cure, making chemical control ineffective. Remove and destroy all infected branches and leaves of crab apples to prevent the spread of disease. If your red jade crab apple has signs of disease, contact your local extension office for advice.

References

• University of Florida: Malus x Red Jade Crabapple
• Colorado State University: Planttalk Colorado Flowering Crabapple
• Colorado State University: Powdery Mildews
• Colorado State University: Flowering Crabapple