2.NounLepidium draba (hoary cress, hoary peppercress, perennial peppergrass, tall whitetop), a perennial herb of family Brassicaceae that reproduces by seeds and by horizontal creeping roots.
"Whitetop is an invasive species in North America."
3.NounRhynchospora colorata (starrush whitetop, white star sedge, white-topped sedge), a plant from the family Cyperaceae.