Perennial ryegrass is a bunch-type grass that is used for winter overseeding on sites where high quality and winter color are needed. The texture, color, and density of perennial ryegrass are very similar to those of Kentucky bluegrass. Perennial ryegrass is often utilized for winter overseeding on golf course fairways and teeboxes, athletic fields, and high profile home lawns. Perennial ryegrass is often confused with tall fescue and/or Kentucky bluegrass. However, Kentucky bluegrass has a boat-shaped leaf tip and distinctive light-colored lines on both sides of the midrib. Tall fescue has rough leaf blade margins whereas perennial ryegrass has smooth ones. Also, tall fescue has rolled vernation in the leaf bud and perennial ryegrass has folded vernation.
Perennial ryegrass is often overseeded to provide winter color in warm climates where turf is utilized in winter months. When warm weather prevails in late spring or early summer, this species usually will not survive. However, in the transition zone, especially during cool summers, wet summers, or both, perennial ryegrass can survive the summer and often becomes clumpy. This very attractive turf species becomes a difficult-to-control weed in these conditions. Control strategies should concentrate on controlling perennial ryegrass before it becomes clumpy.
a spike, with flattened spikelets along each stem
leaves folded in the bud
membranous; collar-like to blunt, may be toothed near top, 0.02 - 0.06 inches (0.5 - 1.5 mm) long
Growth Season/Life Cycle
cool season turf or perennial weed
Leaf blade tip shape
sharp-pointed; bright green, sharply creased, deeply ridged upper surface, lower surface smooth and glossy, edges slightly rough
Leaf blade width
0.08 - 0.2 inches (2 - 5 mm) wide
divided by midrib, not hairy, distinct
sheath is usually flattened, reddish at base