One of the most prolific cool-season grasses, orchard grass is widely used as a forage crop and as ground cover in orchards. It's also one of the top grass allergens in the world.
Habitat: Native to Europe, Asia and North Africa; introduced to U.S. in the 1700s. Prefers cool climates, moist soil and partial shade.
Description: Tall perennial grass reaching 3 to 4 feet in height. Grows in bunches.
Allergy season: May to June
Tips: Grass pollen doesn't travel as far as tree pollen, so windy days tend to be worse. Avoid the outdoors before 10 a.m., keep windows closed and don't use attic fans, especially if you live near grazing land or orchards.