Quercus Pollen

Quercus (oak) is a widespread genus of trees with about 600 species in the Northern Hemisphere. There are 26 species of Quercus trees native to Oklahoma with at least 21 of these species found in eastern Oklahoma. In addition, ornamental oaks are also found in the state. Possibly the two most important species in the great Tulsa region are post oak and blackjack oak. These define the botanical community of eastern Oklahoma. Pin oak, water oak, red oak, and black oak trees are used extensively in landscaping. 

Oak pollen begins appearing in our air samplers around mid-March with the peak concentrations typically occurring during the first or second week of April. Oak pollen levels in the atmosphere are generally high through most of April, and the peak concentrations are often over 1,000 pollen grains per cubic meter of air. By early May, the oak pollen season has ended. Pollen grains are tricolpate or tricolporate with a granular or warty exine.