Thanks for the question.

Unfortunately the production of seeds is a natural event among plants, including ash trees. It has been reported that certain chemicals, such as Naphthalene acid (NAA) or ethephon, are effective in suppressing the production of female flowers and thus seed production. However these chemicals should only be applied by a professional arborist. Furthermore they are very toxic to most pollinators, which is not a good trade-off. Cutting down the trees to deal with seed issues also strikes me as rather extreme. Trees do go through annual cycles in which there might be large seed production over a year or two and then minimal seed production for subsequent years. A year in which there is a large seed production is termed a “mast year”. Reports that I’ve seen indicate that 2022 was a mast year for ash trees in Minnesota. Additionally one of the ways that trees, including ash, respond to stress is to increase their seed production. The hot, dry conditions during the summer of 2022 could have imposed high stress levels upon your ash. They in turn responded by increasing their seed production. I suspect these were factors for your ash trees. See the following for further information on these and related points:

https://holdenfg.org/news/ash-trees-are-exploding-with-seeds-researchers-are-capitalizing-on-it/

https://www.echopress.com/news/why-are-ash-trees-producing-so-many-seeds-this-year - :~:text=Answer%3A Trees produce large amounts,of seeds a tree produces.

https://mortonarb.org/plant-and-protect/tree-plant-care/plant-care-resources/preventing-or-reducing-fruit-on-ornamental-trees-and-shrubs/

In short, most likely you are dealing with a short-term issue. If we do not have a 2023 growing season similar to what existed in 2022, I suspect you will observe a lowered seed production this fall.

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