Can you tell us how we should be trimming the attached back?
Trimming Back Tall Grass Shubs
Certified GKH Gardening Expert
After they've gone brown, you can trim these ornamental grasses at any time. Typically, they should be pruned by cutting them back to about 3-5 inches from the ground any time in the fall, winter, or early spring. To prevent them from dropping seeds that could sprout and cause the grass to spread, you should prune before the seedheads open and drop their seeds.