Sedge grass weed
We have this bright green grass growing in clumps in our yard. They grow fast, and grow where we've put down landscape paper. They are easy to pull up but they come back and they are all over. The blades are triangular, but we don't see nuts when we pull it up? Our neighbors say it is sedge grass.
Nutsedge is a common weed in Delaware, but this year with all the rain we have had, it encourages its growth. Although it looks similar to grass and sometimes called 'nutgrass" it is a true sedge. Sedge will grow through stone mulch, bark mulch and as you know black plastic. It is best to prevent establishment of the sedge and prevent the tubers from developing by pulling it as soon as you see it growing. To control this weed, you must remove the tubers in the ground or deplete them by pulling the top growth or making a herbicide application. There are products available to homeowners, or you may consider hiring a professional to help control this weed. For more information on the life cycle of this weed refer to http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7432.html