Flowers are the reproductive structures ... The hard part is separating the various oak or pine species without looking at additional tree features. Though not technically a part of a tree ...

Apricot trees tend to flower in early spring and need to be protected from late frosts to prevent flower buds falling off.

I recently wrote about pomegranate trees and the fact that although they can survive without irrigation ... (hours between 32 and 45 degrees) to flower and fruit than what a coastal climate ...