Dogwood trees are a beautiful addition to any landscape, but they are susceptible to a variety of diseases that can affect their health and appearance. The good news is that many dogwood tree diseases can be prevented or treated if detected early.
Dogwood Anthracnose
Photo credit: Terry S. Price, Georgia Forestry Commission, Bugwood.org
Dogwood Anthracnose is one of the most common dogwood tree diseases, which typically appears in the spring, causing brown spots on the leaves. Eventually, if untreated, this disease can cause twig dieback, leaf drop, and reduced flowering. The disease thrives in wet conditions, so it is important to keep your tree’s foliage as dry as possible. If you notice the tell-tale spots on your dogwood leaves, call us for diagnosis and treatment. Of course, prevention is the best strategy. Once your leaves are affected, no treatment can erase the damage. After your tree is infected, treatment will serve to prevent the issue from worsening and spreading. New growth will be free of the fungus, but any existing damage on old leaves will remain until next season.
Powdery Mildew
Powdery mildew is another common fungal disease that affects many different plants, including dogwood trees. It appears as a noticeable white or gray powder on the leaves. It is most common in warm, humid weather conditions. While this disease is less severe than others, it can cause serious aesthetic issues, especially on ornamental trees that are prized for their beauty, like dogwoods. Young plants may also be more likely to succumb to this disease, if untreated. Without treatment, powdery mildew can eventually lead to yellowing and curling of the leaves, early leaf drop, reduced flowering, and slow growth. If you notice powdery mildew on your dogwood, call us for diagnosis and treatment. Removing fallen leaves and disposing of them is also a good idea, to prevent the spread of powdery mildew, as many other plants are susceptible to this fungus.
Leaf Spot
Photo credit: Elizabeth Bush, Virginia Polytechnic Institute and State University, Bugwood.org
Several different fungal leaf spot diseases affect dogwood trees. Usually, the symptoms of leaf spot include small, circular spots on the leaves or flowers that gradually grow in size. Leaf spot diseases, like many other fungal issues, thrive during wet spring seasons. While leaf spot diseases are usually not severe and don’t warrant treatment, it’s important not to confuse the symptoms with those of more serious fungal issues which should be treated promptly.
Leaf and Petal Blight
The type of leaf and petal blight that affects dogwoods is caused by a fungus that is common in wet spring seasons. It appears as dark spots on the flowers and gray, fuzzy substance on the leaves and flowers, which can eventually spread to twigs. Luckily, this disease is also not a serious health concern, although it can pose a threat to aesthetics since the flowers are impacted. We typically do not recommend treatment for this condition, since it eventually corrects itself once the summer season comes around.
Cankers
Cankers are fungal infections that cause the bark of the tree to discolor, peel, and crack. They are often caused by fungal spores entering wounds in the tree, caused by poor tree maintenance practices, such as improper pruning or damage to the bark. To prevent cankers, make sure your tree is pruned correctly and not damaged by mowers or other equipment. If you notice cankers on your tree, remove any affected branches immediately. There is no treatment for cankers once the disease is detected, so prevention and proper maintenance is key. Healthy trees are less likely to succumb to cankers, so applying a Bio-Stimulant twice a year can help prevent this issue.
Dogwood trees are a beautiful addition to any landscape, but they do require proper care and attention to keep them healthy and looking their best. Staying vigilant for signs of common dogwood tree diseases is important but can be time-consuming and confusing. We recommend a Canopy Protection Program, which ensures an expert is on your property multiple times a year to look for and address these issues with their trained eye. Also remember to always practice proper maintenance techniques such as pruning correctly and keeping your tree well-irrigated. These tips will ensure you can enjoy the beauty and benefits of your dogwood tree for years to come.
