Knowing the species of tree is helpful in determining which ailments it is most vulnerable to, though we can't positively ID the tree from this photo. Our best guess based on general foliage characteristics is Hackberry (Celtis occidentalis). Hackberry, plus many other trees, are susceptible to several "leaf spot" type infections and other minor ailments that do not require treatment. They also do not harm the tree's long-term health and can usually be ignored. This time of year in particular, leaves tend to look ragged, "burnt," and damaged in other ways that are not consequential for the tree, since they are about to be shed for autumn. In fact, a few of the leaf-spotting fungi are simply taking advantage of the already-dying leaves the tree has sealed-off from its twigs and are starting to decay them, a natural process that helps recycle nutrients back into the soil.

Pesticides used on trees must be chosen with care and used for very targeted reasons, for a particular pest or disease that warrants treatment, since such chemicals would otherwise risk impacting a wide variety of other organisms. Given that, we rarely recommend tree treatment, and even when warranted, fungicides would need to be used preventatively; they cannot cure existing disease. Fortunately, serious tree diseases tend to present different symptoms than those pictured and should be evaluated by a certified arborist to determine how to intervene, if intervention is possible.

We suspect the tree pictured will leaf-out normally next spring and not be significantly affected by whatever caused this type of leaf damage. The drought this past season that stressed many plants likely played a role in its current appearance, at least if this tree was not monitored for watering needs or was a wild tree that was impractical to irrigate based on size or location.

Miri