Here is a tool via Anita Clevenger. The Japanese grass sickle saw is an inexpensive tool that will really save you a great deal of time when it’s time to cut back your ornamental grasses. There are many models, but the one Anita bought at Home Depot is unique in that the inner blade is a fine-toothed edge that is extremely sharp—I mean really, really sharp. Wear a substantial glove with the hand you use to grab a bunch of grass and slice off that bunch with a careful quick pull. The one model I found on Amazon with a finely serated edge is the “Hounenkihan Japanese Grass Sickle Saw” and runs $16.99. Remember to count your fingers when you finish the job. You may have left something behind.
Stan, The Tool Man
Japanese grass sickle