My Cryptomeria Japonica Is Turning Brown

Identification

• Cryptomeria japonica is susceptible to phomopsis twig blight disease also referred to as nursery blight and cedar blight. The infection is caused by Phomopsis juniperovora.

Symptoms

• The disease is characterized by the appearance of yellow spots on the tips of younger and older needles. The infection spreads from the tip to the base of needles and stems, causing dieback. Affected areas gradually assume brown to gray colors and eventually die. In severe cases, stems develop cankers. Small, black fungal fruiting bodies are often visible on affected sites.

Management

• Use resistant tree varieties to reduce chances of infection. Plant trees in well-drained soil and avoid the use of overhead sprinklers. Fungicidal control options include the use of copper based fungicides, mancozeb and thiophanate-methyl.