Horse Chestnut Tree

Answer 1

This article will help you:

https://www.gardeningknowhow.com/ornamental/trees/tgen/fruit-tree-sterilization.htm

There are some sprays available to prevent ornamental trees from fruiting as well. However, what exactly is available varies by state, and results may vary by tree species, so check at a local gardening store or with a local university extension agent for your options.