How to Identify Rye Grass

Ryegrass can be broken down into two major categories, perennial ryegrass, or lolium perenne, and annual ryegrass, or lolium multiflorum. Although they belong to the same species, the two varieties differ greatly from color to shape and size. Both can be found in lawns throughout the country, but perennial ryegrass is preferred for use in pastures and meadows for feeding livestock. Annual ryegrass, however, can be detrimental to pastures and its preferred use is for overseeding lawns.

• 1

  Measure the width of the grass blades. Perennial ryegrass will be between 1/16 and 3/16 of an inch wide. Annual ryegrass will be between 1/8 and 1/4 inch wide. While measuring, look at the shape of the blade. If the blades curve and almost roll into a circular shape, it is most likely annual ryegrass. If they are flat and taper to a point, it is most likely perennial ryegrass.

• 2

  Inspect the color of the grass. Annual ryegrass is a vibrant, lime green color and very shiny. As you get closer to the base of the grass blades, you may notice that the color changes to a slightly reddish color. Perennial ryegrass is a paler green color that remains constant throughout the blade and stem.

• 3

  Measure the height of the grass. Annual ryegrass can grow as tall as 3 feet, but perennial ryegrass will generally grow between 2 and 6 inches in height.

• 4

  Check the grass for spikelets, awns and glumes. Spikelets, as their name indicates, are thin, spike-like protrusions that grow from the blades of grass in an upward angle. Glumes, which also grow from the blades of grass, are soft, bushy leaflets. Awns grow from the glumes and are soft and almost hairy protrusions. If your grass lacks awns and spikelets, it is most likely perennial ryegrass. If all three are present, it is most likely annual ryegrass.