Identifying features of linum aristatum
include the fused rather than separate styles, the glandular teeth along the sepal edges, and the sepal tips, which taper smoothy to a brown bristle. The five sepals are narrowly lanceolate in shape, greenish or reddish, with lighter margins, and about a third of an inch long. Petals are slightly longer, yellow to orange-yellow, obovate, sometimes flushed with red at the base. Upper petal margins are slightly uneven. Stamens are yellow, the styles yellow and the spherical stigmas greenish-yellow.
The very narrow, grass-like leaves are linear, opposite at spreading at the top of the stem, otherwise alternate and ascending, or appressed. Stems are much branched, rigid, and hairless.