Acer Pollen

Acer is a genus of trees mainly found in the Northern Hemisphere. Several Acer species are native in Oklahoma, and the most common native maples are red maple (Acer rubrum), silver maple (A. saccharinum), and boxelder (A. negundo). 

Acer flowers are amphiphilous, which means the pollen is dispersed by both insects and by wind. The pollen grains are tricolpate with long colpi that almost reach the poles and are 25-35 µm in diameter. The exine ornamentation on most species is striate. Silver maple is often one of the earliest trees to flower in the Tulsa area, typically in February; however, we have even seen flowers in January. Red maple and boxelder normally start flowering in March.