Can a black plastic cover over the soil control bermudagrass and nutsedge?

Maybe yes, maybe no, a black plastic cover over the soil will control bermudagrass [Cynodon spp] and nutsedge [Cyperus spp]. Till the soil first. Then put the cover in place. Many weeds don't make it when they're deprived of light and moisture. But perennial weeds such as bermudagrass and nutsedge may require layers of newspaper under the cover. Otherwise, they've been known to break right through the plastic in their search for moisture, light and air.