Tree pictured in the middle stopped me in my bicycle tracks. Wild colors and bark expressions. I think it's an American Sycamore (Platanus occidentalis). It's a serene park today, but not so long ago humans waged a war here... against invasive plants:
Garlic mustard was hand pulled, bagged and hauled away; Oriental bittersweet was treated by cutting the larger vines <2 inches from the ground and immediately stump treated with the appropriate herbicide, followed by foliar application to all bittersweet foliage no higher than three feet. Other species that were low lying were foliar sprayed. Several tree species were also basal bark treated. Recent treatments have included management in riparian areas of Rock Creek for lesser celandine, mile a minute, Microstegium and porcelain berry.