Are you noticing spots on your leaves or mushrooms growing around the trunk of your tree? Do your apples have unsightly brown blotches on them. Then they may have a fungal or bacterial disease and without proper treatment the tree could be permanently damaged or die. It’s important to be able to spot the disease early before it spreads and take proper action.
A fungal disease that affects hundreds of trees and shrubs. The fungus thrives on old logs and rotten stumps and helps with decay but healthy trees in close proximity can become infected by the spores. An infected tree may live several years with the infection but the slow progression of root rot makes the tree weaker and susceptible to strong winds. Signs of Armillaria Root Rot are yellowing leaves, branch/twig dieback, and mushrooms growing around the base.
Easily identified by hard, rough, black growths on tree branches, Black Knot infects cherry and plum trees. The fungus grows slow and can take a full season to become apparent. As it grows around the branch it strangles it resulting in poor fruit growth and stress on the tree. The disease is spread when the knot releases spores on rainy days and are carried on the wind to other trees. The best way to fight Black Knot is with a combination of pruning and fungicide.
A bacterial disease affecting cottonwood, elm, ash, box elder, aspen, poplar, and oak trees. It’s caused when sap oozes out of a tree through a wound caused by pruning, wood-boring, or natural cracks insects and is infected by the bacteria. The sap can turn toxic, bubbly, and have a bad odor. The bacteria grows on the sap and into the tree. Although permanent damage to the tree is uncommon, if the tree is under stress from other factors it can lead to leaf yellowing and dieback.
Another fungal disease affecting juniper, fir, hemlock among others. The fungus spreads in wet conditions caused by overwatering, poor drainage, and wet weather. Signs are reddish brown leaves and black spores at the base of needles. The fungus prefers to attack young, new growth and usually does not affect older growth.
Symptoms are first observed in spring as green or brown spots on the leaves of apple and crabapple trees. The spores are spread from leaf to leaf through dripping water when it rains or carried by the wind to other trees. Severely infected trees will lose foliage by mid-summer leaving them vulnerable to insects and other diseases. To prevent the spread of disease be sure to plant disease resistant varieties of apple trees.