Slategrass

This large, yellow-green grass grows up to 5 feet (1.5 meters) tall. The broad, flat stalks grow in small clumps that are strong.

When mature, the end of the stem eventually transforms into a medium-sized, slate puff.

During the early summer, it produces copious amounts of pollen,but it does not cause many allergic reactions, and after flowering, it is left with lots of large grains.