Cornus kousa IDed by camouflage-like bark and ovate leaves with wavy margins and arcuate venation. Each cluster of tiny flowers is surrounded by four pointed bracts. On this tree, the bracts are green but they turn white. Kousa dogwoods are monoecious.
Honey Locust
Gleditsia triacanthos IDed by plated bark with lenticels, pinnately compound leaves, and racemes attached to leaf axils on the younger branches. Honey locusts are polygamo-dioecious.
Spindle Galls on Linden
Spindle Galls caused by Eriophyid mites IDed by comparing images of galls to the specimen.
Willow Oak
Quercus phellos IDed by long, oblong leaves, usually stiff, with prominent midribs; smooth leaf margins that tuck slightly down; gray crusty bark with relatively smooth, light gray branches; light green new growth with white lenticels. I found it quite hard to ID this tree in the winter, but the leaves give it away. The bark is actually very distinct, especially at the age of most of the NYC willow oaks: it tends to be really rough and brownish at the base and becomes smoother and grayer a little further up.
The leaves look like willow leaves but they are not serrate and their tips have short bristles
Japanese Cherry Extrafloral Nectaries
Prunus serrulata leaf IDed by ovate shape, dark green color, light green underside, serrate margins, and two nectar glands on the petiole at the base of the leaf,
Leafing Thornless Honey Locust
Gleditsia triacanthos IDed by bipinnately compound leaves and plated bark.
Bloodgood Japanese Maple
Acer palmatum IDed by distinct dark red spring foliage; rounded crown and overall shape; maple-like, deeply lobed palmate leaves with 5-9 tipped leaf blades and serrate margins. I also referenced Columbia University’s listing of trees. You can tell it’s not another Japanese variety because this tree is whole-leaf not lace-leaf (the leaves have a flat surface and are not feathery).
American Sycamore
A particularly thick Platanus occidentalis IDed by white bark at top and scaly brown bark at the base.
Blurry Dry Linden Bract
A long, dry flower bract of a Tilia americana, or perhaps a cordata.
American Elm (?)
Ulmus americana (or at least some kind of elm) IDed by shingled, reddish brown buds; drooping, light green, flat, dry, pubescent seeds in clusters; furrowed gray bark. Featuring a Japanese cherry blossom in my hand 🌸.