Did you know there are many diseases that plague trees all year round? 

The Minnesota area is home to a diverse range of tree species, but unfortunately, these trees are susceptible to various diseases. Common tree diseases can have a significant impact on the health and vitality of your trees and plants. These diseases are often caused by fungal pathogens, bacteria, or environmental stressors, and they can lead to leaf discoloration, defoliation, dieback, and even tree mortality. 

Recognizing and understanding these common tree diseases early on is crucial for effective management. Don’t let all the work you’ve put into making your garden beautiful be in vain. Save the trees in your garden and promote healthy growth with our expert tips on how to identify and prevent some of the most common tree diseases.

Common Tree Diseases

Anthracnose

Read Our Other Blogs

Anthracnose is a disease very commonly seen in North America on deciduous trees, such as Oak, Sycamore, Maple, and Ash trees. It is a fungal infection that causes dark brown lesions on the twigs, shrubs, flowers, leaves, and fruits of trees. Since this disease spreads through water, it occurs more frequently during the wet, cold spring months of the year. If you think your tree is suffering from anthracnose, make sure you remove all the fallen and dead twigs, leaves, and branches, and prune the tree well. 

If you’re still unsure whether your trees are suffering from anthracnose, contact us and one of our trained arborists will be happy to help you. 

Apple Scab

As the name suggests, apple scab is a type of tree disease that affects apple and Crabapple trees, along with pear and mountain ash. The fungus infects the fruit and leaves and causes scab-like lesions all over. This not only makes them dangerous to eat but causes the tree to look scrawny. The best way to treat apple scab is to ensure that all the dead, infected foliage is raked and removed. This prevents the fungus from spreading to healthy parts of the plant and causing more damage. 

To protect your plants from apple scab, it is best to use disease-resistant apple varieties. Our Birch Tree Care specialists will be happy to help you go about this process and provide you with the right apple-scab fungal sprays for your trees.

Fire Blight

Fire blight is another disease that affects apple and pear trees. If your tree has been infected, you’ll know - the tree branches look like a fire has scorched them. This bacterial infection attacks the twigs of the plant most commonly in warm, moist weather. Even though fire blight has no miraculous cure, the best way to keep this disease under control is to remove and destroy infected branches. 

Pro tip: Make sure you disinfect your pruning tools when cutting off the infected parts of the tree. Since fire blight isn’t something you can cure, our trained specialists will be happy to help contain it and keep your landscape disease-free. 

Cedar-Apple Rust

As the name indicates, cedar-apple rust is a disease found on Oak, Hawthorn, and Crabapple trees. While this infection won’t kill the trees, the disease weakens them. It first attacks cedar trees, and then the following year spreads to apple trees through spores in the air. This causes major leaf damage and hinders fruit production. 

The best way to identify this tree disease is to look for bright yellowish-orange spots on the leaves. Leaves, twigs, and fruit might also start shedding prematurely. The only way to prevent this disease is to use sprays with fungicides, liquid copper, or bio fungicides, as they stop the spores from infecting apple trees. You can also stay one step ahead of the game by planting disease-resistant varieties. If you want to know how to go about this, contact us today.

Oak Wilt

Oak wilt is a fungal disease that is most prominent in red oak trees, but white oaks are also susceptible to it as well. The trees rapidly wilt, starting from the top to the bottom, turning brown. 

There are two ways oak trees get infected: through root-to-root contact, and through beetles feeding on the sap. To learn more about oak wilt and how they affect your trees, check out our detailed article here. If you need professional guidance, contact us and we can connect you with a trained arborist who will give your trees oak wilt root flare injections. 

Any tree disease control and prevention starts with regular monitoring. Recognizing the signs early on helps reduce the severity of the disease and fends off future damage. Identifying these common diseases and their causes should help your plants thrive with a long and healthy lifespan. 

If you’d like to know more about plant diseases and how we can help, check out our treatment guide below, or contact us for inquiries.