A portion of an aspen stand showing many leaves dropped due to drought, taken Sept. 2, 2026. / Photo Credit: Wisconsin DNR

By Linda Williams, DNR Forest Health Specialist, Woodruff
Linda.Williams@wisconsin.gov, 920-360-0665

Drought impacts can show up abruptly or have a slower impact, with symptoms becoming visible over the next one to two years.

North central and northwestern Wisconsin have faced significant drought conditions over several months this summer.

Some trees have reacted abruptly to these conditions by dropping many of their leaves, and fall color appeared to come early on many stressed trees.

Areas circled in yellow show a young aspen stand with grey/yellow areas where trees have dropped leaves or are dropping leaves due to drought in August 2026. / Photo Credit: Wisconsin DNR

While conducting an aerial survey, it was noted that some young aspen stands had large areas of trees that had dropped many of their leaves. Checking these sites found lots of dry, dead leaves on the ground. Those leaves had not dropped due to disease or physical injury, so drought is the next logical reason.

Some trees purposefully drop leaves during droughts to preserve water within the tree. These young trees, which are vigorously growing, are expected to bounce back just fine next year. However, the most severely stressed of the aspen may be attacked by our native bronze poplar borer, a beetle that can attack stressed aspen.

Landowners and professionals are advised to monitor forests that were severely impacted this year to see how they leaf out next year.