My tall fescue seed is contaminated with another grass. What is it and what do I do?
In late fall and early winter, areas previously seeded to tall fescue often contain grass that is taller, broader, and shiny. This grass is usually Italian ryegrass (a.k.a. annual ryegrass, Lolium multiflorum) and is often found as a seed contaminate. Even certified seed allows for a small percentage of “other crop seed” and Italian ryegrass is considered another crop. It’s hard to differentiate tall fescue seed from Italian ryegrass seed and fescue seed is often contaminated with Italian ryegrass. There are other ways that Italian ryegrass can infest a newly-seeded lawn. These include indigenous seed in soil, wind blown seed, and Italian ryegrass plants or plant parts that were not completely killed during the renovation. However, Italian ryegrass plants that are uniformly spaced throughout the seeded area most likely came from contaminated seed lots. This contamination is very evident before the lawn is mown but is of little consequence to the homeowner as long as the Italian ryegras
