Over the last several weeks, gardeners across the state have noticed hackberry trees shedding an alarming number of yellow leaves. These yellow leaves are dispersed throughout the canopy, and while many of the leaves look a little ragged, they show no clear signs or symptoms associated with insect or disease activity. The concern is understandable when you see the ground under your favorite hackberry littered with yellow leaves, however, this symptom is not a sign of tree decline.
Why It Happens
This type of leaf drop is a normal response to changing weather conditions. In years with favorable early-spring weather, trees like hackberry produce abundant foliage. This April, moderate temperatures and abundant rainfall were particularly conducive for leaf production.
But with the arrival of warmer, drier conditions in May, trees dropped leaves that could no longer be supported. In other words, leaves are shed to balance the water needs of the plant with available moisture. This process helps the tree conserve resources and maintain overall health.
Early-season leaf drop on hackberry is a fairly common occurrence, and in some years it is more noticeable than in others. It seems 2026 is one of those years.
What About Spots and Ragged Leaves?
Fallen hackberry leaves often show bumps, spots, or holes, which can add to concern. These symptoms are normal for this species.
The bumps are caused by hackberry psyllids and are so common that they are often used to help identify the tree. Holes and ragged edges are caused by caterpillars of native moths and butterflies such as mourning cloak, question mark, and eastern comma, which rely on hackberry as a host plant. They make the foliage a little ragged, but they don’t harm the tree.
Other Trees That Do This
Hackberry is not the only species that may drop leaves in late spring or early summer. River birch, boxelder, elm, and tulip poplar often display similar responses when weather conditions change.
What To Do
No action is needed. This is a natural and expected condition, and trees typically return to a normal appearance within a few weeks. They don’t produce new leaves to replace those that have fallen, but those that remain gain in size and weight, eventually returning tree canopies to a full and healthy appearance.
Monitor the tree over time. If leaf drop becomes uneven, affects only certain branches, or is followed by dieback, further evaluation may be needed. Use this article to help: How to Diagnose Problems with Trees in the Landscape.
Otherwise, this early summer leaf drop is a normal adjustment to seasonal conditions.
More Information
Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Yard and Garden, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on June 8, 2026. The information contained within may not be the most current and accurate depending on when it is accessed.