Your prized apple blossom trees that produce beautiful blooms and delicious fruit in your home garden are susceptible to invasion by fungal pathogens that lead to the rot of your trees' wood. Once the wood of your apple blossom tree decays, there is no cure to reverse the damage, so close observation and care are needed and offer preventive protection.
Strong, vigorous apple blossom trees have an increased potential for fighting off or resisting wood rot attacks when compared to stressed, poorly maintained trees. Grow apple trees in areas that offer full sunlight for best growth and successful blossom and fruit development, according to the AgriLife Extension Texas A&M System. Sun exposure during the morning hours is particularly important as the sun aids in drying dew on plant surfaces, whereas standing water creates a prime environment for the proliferation of wood rot fungi. Apple blossom trees thrive in extremely well-drained soil as waterlogged soils decrease root function and also promote fungal germination.
Varnish fungus rot is a fungal infection of apple blossom trees that leads to wood rot. This disease is caused by the fungal pathogen Ganoderma lucidum and is primarily attracted to stressed, injured trees, according to the University of California IPM Online. Turkey tail wood rot is another fungal infection that affects apple blossom trees, caused by the fungal pathogen Trametes versicolor. Fungi inhabit plant debris and invade through wounds of injured trees.
Varnish fungus rot leads to the display of red/brown conks on apple blossom trees. Typically appearing on the base of trunks, conks are shelf-like fungal growths that resemble mushrooms. These conks reach a width of 14 inches, according to the University of California IPM Online. Both the root system and the internal wood of the tree trunk rot and change to a white color. Apple blossom trees face plant death within three to five years of infection. Turkey tail wood rot of apple blossom trees results in cankers, or lesions of dying plant tissue, on tree surfaces as well as bark that takes on a paper-like texture. Clusters of small conks measuring up to 4 inches in width appear on the trunk while internal wood rots and takes on a white, cushioned form. This disease is aggressive and leads to tree death.
Fungi spread sporadically on wind and rain and inhabit soil. When choosing plants for the landscape, it is best to avoid other highly susceptible trees to prevent the continuation and further spread of fungal pathogens. To avoid counterproductive landscape design, avoid susceptible trees to varnish fungus rot and turkey tail. Vulnerable trees include, but are not limited to, ash, birch, citrus, elm, maple and willow, according to the University of California IPM Online.
Fungicides are ineffective in controlling wood decay in apple blossom trees and will not cure an existing problem, according to the University of Arizona Cooperative Extension. For management of both varnish rot fungus and turkey tail wood rot, maintain vigorous trees free of wounds through which fungi invade. For mild infections, remove and destroy affected plant parts; always sanitize pruning tools between each cut and from one apple tree to the next to prevent disease transfer. Contact a licensed professional for an assessment of your trees to determine their safety. Internally rotted trees may suddenly collapse, posing a threat to animals and people. For severely infected trees, remove the tree and do not replant with a susceptible variety.