3 Common Tree Diseases that will cause leaves to "Fall" early this year:
Here are the 3 common tree diseases that are in full affect this season and treatment options:
Anthracnose is caused by a group of fungi that attacks leaves, twigs, flowers and fruits of a great number of tree and shrub diseases. It can be found throughout various species in most of North America, but important species to keep watch on are sycamore and flowering dogwood.
Anthracnose symptoms vary by the pathogen and host species. Sycamore anthracnose causes premature leaf defoliation and a twig blight resulting in witches blooming. Dogwood anthracnose is common on flowering dogwood in the Eastern U.S. and western flowering dogwood in the Pacific Northwest. All above-ground parts of the tree may be attacked, resulting in defoliation, branch dieback and tree death.
Control: For management of sycamore anthracnose, begin foliar applications of fungicides two weeks before bud break. Alternatively, trunk inject with a systemic fungicide. The most effective active ingredient is thiabendazole. In the case of dogwood anthracnose, foliar applications must begin at bud break and continue all through the growing season to protect the tree. For dogwood anthracnose, propiconazole is an effective fungicide. Good sanitation practices can also help reduce disease inoculum.
2. Apple scab
Apple scab is an early season leaf disease affecting crabapples. Some crabapple cultivars are more resistant than others. Scab-like lesions form on the leaves that eventually cause premature defoliation of infected trees.
Control: While mostly aesthetic, homeowners may find apple scab objectionable. It can be managed with fungicide applications with active ingredients, such as fenarimol, beginning at budbreak.
3. Cedar rusts
Cedar rusts are common foliar diseases of rosaceous plants, such as hawthorn and crabapple. As with apple scab, some cultivars and species are more susceptible than others. Rust diseases require junipers as an alternate host. Orange or rust-colored leaf spots form on hawthorn and crabapples in the spring. Twig cankers can develop and cause dieback. Spore-producing structures form on the juniper branches.
Control: The disease can be managed with fungicide applications on the deciduous hosts beginning at budbreak or when orange spore masses develop on junipers. An active ingredient for controlling rust diseases is triadimefon. Prune out rust galls on junipers when noted.