Ornamental grass maintenance
Should ornamental grasses such as Mexican feather grass, blue oat, and large and small blue fescues be cut back in early spring before new shoots appear?
Boulder County Colorado
Certainly, you're safe cutting back the old foliage before the new foliage appears in the spring, however, with those particular grasses, some people prefer to simply rake out the old foliage using a comb or by massaging the blades while wearing rubber gloves.
The Mexican Feather Grass (Nassela tenuissima) produces an enormous amount of seed which self-sows to the point of making itself a weed. Raking it after it blooms gets rid of a lot of that seed and leaves behind only the soft culms to blow in the breeze.
The fescues tend to be short-lived and need frequent division. Oftentimes, teasing out the spent blades is enough to tidy up the plant without going to the extreme of cutting it all the way back.