I think I have something called ornamental grass (gardening newbie). There seems to be clumps of it in one section of my garden. I have dug a few up as I don't really like it. But I've never grown it. Is it like a weed?
It can spread like weeds and has a pretty extensive root system . They are a nightmare to dig out as any little bit of root left will regrow into a whole new plant. Roundup will kill them without damaging the soil but will probably take several applications depending how large the clump is.