Tree disease and pests can have devastating effects, targeting different parts of the tree including the roots, trunk and branches. Diseases that affect the tree’s leaves may seem like a minor issue but can result in major consequences and can be detrimental to the overall health and appearance of the tree. That’s why it’s important to know the different types, how to spot and how to manage them.
Bacterial Leaf Scorch
Bacterial Leaf Scorch is caused by the bacteria Xylella fastidiosa and affects large variety of shade trees such as maple, oak and elm. It has been most commonly found in southern states but in recent years seems to be creeping north, toward the Upper Midwest. It is spread by small bugs that carry the bacteria and feed on the leaves of trees.
How do I spot it? It can be difficult to identify Bacterial Leaf Scorch because it can be so easily mistaken for other tree diseases and environmental stress indicators which cause the appearance of brown edges. The first signs of the disease come in late summer and can slowly spread throughout the canopy to the branches, slowly killing the entire tree.
Phyllosticta Leaf Spot
Phyllosticta leaf spot is caused by a fungus and is found on maple trees. The spores that carry the disease are transferred, believe it or not, by the wind. If you spot this disease on your maple tree, be sure to rake the leaves after they have fallen so it doesn’t continue to spread. Fungicides can also be applied but be sure they have the correct active ingredients.
How do I spot it? The disease can be identified by the appearance of yellow spots that have purple edging, appearing during the spring and summer months. The spots will begin to darken and the canopy will begin to lose its leaves.
Aspen Blotch Miner
Aspen blotch miner is an insect that feeds on leaves between the surfaces. These insects cause blisters that have a round appearance that are light at first but darken over time. They become fully grown toward the end of July and beginning of August. It is not detrimental to the tree, though it may cause some defoliation.
How do I spot it? Although you might be able to spot the pests by the appearance of your tree’s leaves, they can also be detected by the shedding of the tree’s bark. Also known as aspen leafblotch miner, these pests often shelter themselves beneath the trees bark during the winter, only to be eaten by birds over the winter. Although this does not rid the tree of the pests, it is a good indicator of their presence.
Managing Leaf Diseases
Want to know how to manage leaf diseases and pests and even prevent them from occurring? Follow the tips below. You can also find details about leaf disease management, as well as information about additional types of leaf diseases, here.
- Select trees that are bred to be resistant to diseases.
- Provide your trees with room for circulation and avoid placing a tree that is susceptible to disease and requires a second host plant to complete its life cycle close to each other.
- Prune and trim your trees regularly to reduce infection by passing spores and to improve air circulation.
- Consider implementing a fungicide routine.
If you suspect that a tree on your property has a leaf disease or pest and aren’t sure what steps to take next, contact Ostvig Tree Care. We can offer you a free consultation and are happy to help ensure the livelihood of your landscape.