Cyptomeria (Cryptomeria japonica) belongs to the cypress family and has a mature height of about 100 feet. The blue to bright green foliage is evergreen and assumes brown shades during very cold weather. A fungus causes cryptomeria to turn brown.
Blight, also referred to as cryptomeria blight, is a pathogenic disorder of cryptomeria tree. The fungal disease is caused by Pestalotiopsis funerea.
Infected trees initially turn yellow and then start to brown. The discoloration starts at the tip of the foliage and then moves inward. Blight most affects the lower and older foliage of the tree. The fungus is more prevalent in trees that are growing poorly and are already under stress.
Plant trees in areas of good air circulation and sunlight. Avoid keeping foliage wet for extended periods. Chemical control options include the use of blight fungicides including thiophanate methyl and mancozeb.