Camellia Leaf Spots

Types

• Camellia foliage is susceptible to fungal, algal and viral leaf spot infections. Sudden oak death is a fungal disease of several tree and ornamental species, including camellia. The fungus spreads from camellia and other host plants to nearby grown oak trees. While the disease is serious for oak trees, it rarely kills otherwise healthy camellias. Algal leaf spot is a common disease caused by a parasitic alga. The algae can overwinter on infected and fallen plant tissue, which can cause perennial infection. Camellia yellow mottle is a viral disease that affects the foliage of camellia.

Symptoms/Identification

• Sudden oak death produces yellow to dark brown leaf spots on the tip of the infected leaf. As the disease progresses, the spots enlarge to the inner margins of the leaf and leaf drop occurs. While the disease is fatal to oak trees, it rarely causes a fatal infection in camellia. Symptoms of algal leaf spot consist of gray to green circular leaf spots on leaf, twig and stem surfaces. Severe infections cause leaf yellowing and premature leaf drop.

  If the infection occurs in the twig and bark area of the plant, it can cause girdling and plant death. Symptoms of camellia yellow mottle virus consist of irregular yellow leaf spots, entire leaf yellowing and blotching on blossoms. Mild to moderate infections only cause superficial damage, while severe infections cause extensive leaf yellowing and reduced plant vigor.

Favorable Conditions

• The sudden oak death fungus spreads through infected soil, splashing water and windy weather conditions. The algal leaf spot pathogen favors splashing water and free moisture on leaf surfaces for infection. Algal infections are common on stressed and unhealthy plants. Yellow mottle virus transmits through infected root grafts and breeding of diseased plants.

Management/Control

• Fungicides are an effective method of prevention for the sudden oak death fungi. Burn and bury infected plant tissue to prevent the fungus from spreading and to reduce the severity of the disease. Copper-based fungicides can help reduce the severity of algal leaf spot infections, while pruning overgrown branches and maintaining plant vigor can prevent the disease. There is no cure for camellias infected with camellia yellow mottle virus.