Brass buttons is a slender, branching, inconspicuous winter annual that seldom grows over three to four inches tall. Its tiny leaves are finely cut into slender tapering parts. This entire plant is extremely small and weak in appearance. Brass buttons has a tendency to grow in clumps, but plants may become so thick that they are interspersed through the entire lawn. The flowers of brass buttons are about the size of a pencil eraser. They are yellow-green in color, and grow singly on stems that extend slightly above the prostrate leaves.