LawnAmerica Photinia Program
Controlling Leaf Spot on Photinias
Photinia is a common shrub in the Bartlesville area, belonging to the rosaceous family. Several species, including Photinia serrulata and Photinia glabra, and a hybrid, Photinia x fraseri, are grown for landscaping. Because of its bright red, immature foliage, Photinia x fraseri, also known as “red tip,” is the most popular photinia grown. While Photinia is a fast-growing and beautiful shrub, all of these ornamentals are susceptible to leaf spotting caused by the fungus Entomosporium mespili.).
Symptoms
Leaf spots on photinia first appear as minute, slightly raised dots on either surface of the leaf. Older spots have a slightly depressed center with raised margins. The centers of the necrotic spots are dotted with minute black specks, which are the spore-producing structures of the fungus. Leaf spots are discrete in light infections, but in heavy infections they often coalesce to form large dark red to black spots and blighted areas.. Heavy infections cause premature defoliation and even death of the plant.
Leaf spots on photinia caused by Entomosporium mespili.
Disease Cycle
The fungus overwinters as mycelium in fallen infected leaves from the previous year. In the spring the fungus produces spores that are dispersed by splashing water to healthy tissue. Symptoms first appear on the new growth of the lowest branches and spread gradually upward. The fungus continues to sporulate throughout the growing season. Excessive rainfall or irrigation on the leaves will increase the severity of the disease.
Control
Cultural Control
Collect fallen leaves in the winter to reduce sources of fungal inoculum before new growth appears in the spring. Plants pruned in late summer may suffer infections on resultant new growth into the fall. Avoid frequent pruning and over-fertilization, which stimulate succulent growth.
Chemical Control
Fungicides can be used preventatively, but they must be applied on a regular basis throughout the season for effective control. Our Photinia Program provides 3 timely applications of a fungicide which will help combat Leaf Spot Disease. The first application is applied in late March or early April at bud-break, and the following applications are spaced at 4 week intervals.
For more information on LawnAmerica’s Photinia Program or to sign up, please fill out the service request form below or call 918-332-6299.
