|Species in the grass family (Poaceae) have narrow grasslike foliage, with leaf veins typically parallel to one another, and the leaf margins are most often smooth. With a few exceptions, such as bamboo, most grasses are herbaceous, meaning they do not develop woody tissues. Roots of grasses form a fibrous mass and enable the plant to survive long-term dry periods. Stems are composed of solids joints, called nodes, serparated by segments called internodes. Nodes are the points of attachment for leaves. Flowers, and later seeds, are borne in spikes, racemes or panicles, on a central stem. Grasses spread horizontally by stolons or rhizomes, and reproduce by seed as well. Fertlizing ornamental grasses can result in over-lush growth and unmanageability. B. caucasia is clump-forming, with sprawling habit after flowering in mid to late summer. Grown for its terminal, purple-pink flower-heads and blue-green foliage.