whitetop

1a (1) :  a redtop (Agrostis alba) (2) :  a grass (Fluminea festucacea) of northwestern North America that is an important source of food for wild birds (3) less commonly white topped grass :  any of several grasses of the genus Danthonia (especially D. pilosa) b :  fleabane c :  any of several Australian eucalypts; especially :  a widely distributed blackbutt (Eucalyptus pilularis) d :  hoary cress

2 :  a covered wagon with a white top