by Sierra Mayle, Animal Sciences major
In the wake of summer, many gardeners and agricultural developers will definitely see what is called leaf spot. Everywhere and common, this is often caused by pathogenic fungi that infect the leaf and once there, grows and grows until leaf tissue is destroyed.
Depending on the severity the leaf can have smaller dots to the entire leaf being enclosed in this fungi. Now, it is important to note that even though these may be common but not necessarily fatal diseases, plants and trees that were already under a lot of stress or not healthy to begin with are much more susceptible.
The fungi will cause degeneration of plant tissues and have the potential to seriously injure if the fungus is not under control. It is difficult to treat once leaf spot have become prominent because with using chemicals on the trees comes the risk of further injuring and lessening the tree’s strength. More information on control can be found on this website: www.ladybug.uconn.edu/FactSheets/leaf-spot-disease-of-trees-and-shrubs.php
Some trees commonly susceptible are maple, oak, walnut, ash, hickory, and horse chestnut. There are a few different fungi that cause this problem, including anthracnose and leaf blister (affecting oak trees). Anthracnose deals with multiple clusters of this species producing the black or brown spots on the leaves. Leaf blister most commonly affects oak trees in cooler spring weather.
We should always watch for leaf spot. There are many varieties of plant, trees, and crops this can affect and through hortweek.com, agriculturalists have been warned to watch for this leaf spot fungi on cauliflower, pink or black lesions appearing on the heads.
Even though this fungus may not be severe on any scale it has the potential to weaken and destroy plant tissue, leaving the unknown possibility for anything to happen . . . maybe even a resistance mutation over time with the repeated use of fungicides trying to fight them?
Sierra Mayle is a third year student at The Ohio State University, exploring animal sciences and plant pathology. In her spare time she enjoys reading and playing with her three dogs and ferret.
This blog post was an assignment for Societal Issues: Pesticides, Alternatives and the Environment (PLNTPTH 4597). The views expressed are those of the author and do not necessarily reflect the views of the class, Department of Plant Pathology or the instructor.