Celtis Pollen

Celtis (hackberry) is a genus of trees and shrubs distributed through tropical and temperate areas on all continents except Antarctica. Four species of Celtis species occur Oklahoma. The flowers are small and inconspicuous with separate male and female flowers in the same tree. 

Celtis pollen grains are approximately 26-30 µm in diameter with 3 (possibly up to 6) pores and a prominent oncus beneath each pore. Starch grains are frequently seen within the pollen grain.