Common Tree Diseases

At Fit Turf, our tree care professionals are passionate about healthy trees. Below, we’ve compiled a short guide to common tree diseases to help you better identify and prevent them on your property. Read on to learn more and contact our Colorado and Michigan tree professionals for disease control and prevention services today!

Anthracnose: Anthracnose is caused by fungi in the genus Colletotrichum. It is characterized by dark, sunken lesions on leaves and stems that can spread to developing shoots. Anthracnose can spread quickly during the rainy season and is typically treated using fungicides and sprays. It is found in the Eastern U.S., including Michigan.

Bleeding Canker: Bleeding cankers are dark, oozing lesions typically found on the trunks of trees. These cankers are associated with the fungal-like Phytophthora species and stay with their host trees for life. The spread of bleeding cankers can be controlled with proper care. It has been identified in poplar trees in Colorado and is also present in Michigan in chestnut and cherry trees.

Diplodia Tip Blight: Diplodia tip blight is a common fungal disease of stressed conifers typically found in trees located in planted in sites with poor conditions. Diplodia tip blight is characterized by the browning and drying out of conifer branch tips and needles. It can be prevented and mitigated with fungicide spray. It can affect Colorado blue spruce, which is native to the Rocky Mountain areas, as well as Ponderosa pine — the most common pine tree in North America. It also affects Eastern white pine, which is found in Michigan.

Fire Blight: Fire blight is a disease of apple, pear and other rosaceous plants in North America. It is caused by the bacterium Erwinia amylovora that attacks several parts of a tree, including blossoms, leaves, shoots, branches, fruits and roots. Fire blight gets its name from the burned look it gives host trees. Careful chemical application during warm and humid seasons can mitigate the disease and prevent further outbreaks. It has been found in Michigan and Colorado.

Rhizosphaera Needle Cast: Needle cast is caused by the fungus Rhizosphaera kalkhoffii. Needles infected with needle cast turn brown or purplish brown in late winter or early spring. The fungicide Chlorothalonil can be sprayed on new needles to prevent needle cast from spreading. It affects trees of the pine classification common to Colorado. It is the most common fungal disease of the blue spruce tree in Colorado and Michigan.

Oak Wilt: Oak wilt is a complex, fungal disease. It is spread by root-to-root contact of trees. Symptoms in red oaks appear as an oily green appearance in the tree’s canopy and rapid shedding of the foliage. Other oak trees’ symptoms are foliage that turns yellow or brown. It affects white, red and other oak tree species, and has been confirmed in both Michigan and Colorado.

Scale Disease: Scale disease is an infestation of sucking insects on the limbs and trunk of a tree. The insects themselves do not look like conventional insects and instead appear to be hard shell-like growths resembling barnacles. Scale disease can be effectively managed with proper insecticide. There are two forms of scale disease: Pine Needle Scale and Soft Scale. It can be found in both Michigan and Colorado.

Pine Needle Scale: Pine needle scale is an infestation of hard, armored aphids. Symptoms include thin, sparse needles, waxy scales covering needles and noticeable branch and needle death. It can be found in Michigan and Colorado.

Soft Scale: Like pine needle scale, soft scale is an infestation of parasitic aphids that sometimes appear fuzzy. Ants can sometimes be a sign of soft scale. Soft Scale can be found in Colorado and Michigan as well.

If you suspect your tree(s) may be infected with any of these tree diseases, contact our tree care professionals at Fit Turf. We have decades of experience dealing with each of these diseases and can provide diagnostics and comprehensive treatment plans that will give your trees the best chance possible at a healthy life. Learn more by contacting our team today!