Apple scab and cedar-apple rust are two fungal borne diseases that can affect your apple tree.
Apple scab appears as circular, olive-black spots on the leaves, fruit and stems. A tree suffering from heavy apple scab infection will show signs of defoliation and suffer from distorted fruit development. The fungus remains on the fallen infected leaves during the winter months and infects new leaves during periods of spring rain.
Certain varieties of apple trees are more susceptible to apple scab than others. McIntosh and Cortland varieties are particularly susceptible, while Liberty, Jonafree, Priscilla, and Redtree have significant resistance to the disease. To control outbreaks of apple scab, remove fallen leaves from the surrounding area of the tree during wintertime to prevent reinfection.
Cedar apple rust is another fungal disease affecting apple trees that stems from red cedar trees being planted too proximally close to apple trees. The fungus needs both species of plant to complete its lifecycle, beginning with its signature bright orange galls on cedar trees that then produce spores carried by the wind to apple trees. Once the fungus has taken host on the apple tree, it produces another spore which is able to re-infect the cedar tree.
Similarly to apple scab, certain varieties of apple trees are more vulnerable to outbreaks from cedar apple rust than others. Delicious, Empire, Jonamar, McIntosh and Cortland are resistant to cedar apple rust. However, Cortland and McIntosh are susceptible to a related fungus, quince rust.
Whether you’re looking to plant orchard variety trees for the first time or are dealing with an outbreak of disease, Eric can help. We advise customers on planting practices and landscaping as well as tree service and tree removal. Call or text us today to schedule your free estimate.