Black walnut...Juglans nigra...the flowers are monoecious. Male flowers (staminate) are dropping catkins and female (pistillate) flowers are terminal in clusters. Family- Walnut ( Juglandaceae). Late spring flowering & Autumn fruit. Edible/medicinal- eat the walnuts, used for treatment of worms, syphilis, leukemia, skin infections. Used to make dyes for hair or painting. My trees will give fruit this year again. They fruit every two years...