Root rot is a common fungicidal disease that occurs in cottonwood and fruit trees. It can occur in any portion of the world. Some varieties of apple trees are prone to root rot; others can fend off the disease. As apple trees get older, they become less susceptible to root rot. Knowing the signs and symptoms will help in determining if a tree is infected. Preventative measures are the only effective way to deal with apple tree root rot.
Two main types of apple tree root rot exist: fungicidal and bacterial. One of the most common types of root rot is phytophthora root disease. Mushroom root rot is also common and gets the name from the mushrooms that form around the base of the tree. Southern blight is another type; it strikes younger apple trees. All types of root rot cause death in infected trees.
Several signs of root rot can show in apple trees. Among them are yellowed leaves and a steep reduction in the tree's growth. White, web-like formations of mycelium will form on the trunk and mushrooms will appear at the base of the trunk. The collapse of the tree can occur over time or during a single year.
Symptoms of root rot in fruit trees, including apple trees, include a reddish-brown coloration of the inner wood in the roots. This can be found by digging out several inches of dirt around the tree and cutting into the roots.
Root rot in apple trees are from soil-borne pathogens and fungus. These vary depending on the type of disease. Trees planted in poorly drained soil, or in areas where the soil is saturated with rain or over-watering, are susceptible to root rot. Many of the pathogens will remain dormant over winter and emerge as infections in the roots, cankers on tree collars or mycelium webs.
Fungicides are the most effective prevention in areas with good drainage. Picking specific varieties of apple tree, such as Ottawa-3 or M-9, will help reduce the likelihood of the disease. Once root rot has begun, fungicides will be ineffective. Planters should avoid placing apple trees in freshly cleared areas or areas where diseased trees have been removed. The only completely effective treatment is removal of the tree.