Why is my tree sad?
It looks like you have a Linden (Tilia spp.). The brown edges were caused by the feeding of Japanese Beetles. LIndens are beautiful with sweetly-fragrant flowers in June, but unfortunately, a favorite food of these insect pests. They won't kill your tree, but they do disfigure the foliage and there are very few options for controlling them because pollinators also love lindens and chemicals - organic or synthetic - used to control the "bad bugs" also will harm the non-targeted "good bugs."
Read more here: https://extension.colostate.edu/topic-areas/insects/japanese-beetle-5-601/