Allergy Information

Flowering with significant pollen shed occurs during July to September and causes pollinosis in these states.

Genus Details

This perennial grass is also called hairgrass, or western June grass. It is an important forage or pasture grass in the western U.S. It grows in prairies, open woods and sandy soils throughout the U.S. , except in some southeastern states. Slender plants are low to moderately tall (1-2 feet tall) with narrow leaves (1- 7 inches long), and glossy spike-like panicles or flowering stalks.

Pollen Description

Grains are spheroidal to ovoidal, sometimes elliptical. The exine is thin and the surface is granular to finely reticuloid. Pocaceae apertures are 1-porate, with the pores usually circular to ovoidal.

Grains are 22-122 micrometers in diameter.

Genus Distribution

The shaded areas on the map indicates where the genus has been observed in the United States.

- Native, observed in a county 

- Introduced, observed in a county 

- Rarely observed