The genus Grayia Hook. & Arn., named for the American botanist Asa Gray, contains a single species - spiny hopsage (table 1). Plants are erect to rounded, summer-deciduous shrubs 0.3 to 1.2 (1.5) m tall. Branches are divergent and thorn-tipped, with whitish gray to brownish bark that exfoliates in long strips. Leaves are gray-green, alternate, entire, and fleshy, sometimes turning bright red before abscising. Pubescence of young twigs and leaves consists of simple or stellate hairs. Prominent globose, gray-green overwintering leaf buds develop prior to summer leaf fall.