While nutsedge resembles a grass at first glance, its size and spiky seed head set this weed apart.
Purple nutsedge grows to around a foot or more in height and is crowned by reddish-purple seeds.
Yellow nutsedge can reach almost three feet and produce yellow seeds.
The weed can also be differentiated from grass by its stems. Where grass stems are hollow and round, nutsedge stems are triangular and solid.