Noun
Any species of Melilotus, a genus of leguminous herbs having a vanillalike odor; sweet clover; hart's clover. The blue melilot (Melilotus caerulea) is used in Switzerland to give color and flavor to sapsago cheese.
Source: Webster's dictionaryAdditional species that have been recognized more recently as aggressive and requiring control are yellow star thistle (Centaurea solstitialis), sweet clover ( Melilot spp. Source: Internet