- black medick, hop clover, yellow trefoil, nonesuch clover, Medicago lupulina - prostrate European herb with small yellow flowers and curved black pods; naturalized in North America
--1 is a kind of medic, medick, trefoil
- hop clover, shamrock, lesser yellow trefoil, Trifolium dubium - clover native to Ireland with yellowish flowers; often considered the true or original shamrock
--2 is a kind of clover, trefoil