Perennials 25-60 cm (dense bushy clumps); taproots deep, vertical, woody. Stems ascending to erect, pale green, striate, often much-branched from bases and distally, glabrous. Leaves: (basal forming rosettes, sometimes withered and absent at flowering) proximal blades linear. 50-70 × 1-2 mm, entire or sparingly laciniate; cauline 40 mm or less, reduced to scales distally. Heads (1-6), borne singly. Involucres cylindric, 14-21 × 4-6 mm, apices narrow. Calyculi of 8-10, ovate bractlets 2-3 mm, margins ciliate (apices often purple, with small appendages, faces glabrous, sometimes roughened). Phyllaries 5-7, linear-oblong, 16-20 mm, margins scarious, faces glabrous, apices appendaged (often dark). Florets 5-7; corollas lavender, 12-16 mm, ligules 5-6 mm wide. Cypselae 11-14 mm, faces smooth, adaxial weakly sulcate, glabrous ; pappi 11-13 mm. 2n = 18.
Flowering Jun-Oct. Rocky grasslands and oak forest, rocky soil, roadsides; 1200-1900 m; Tex.; Mexico (Chihuahua, Durango, Sonora).
Lygodesmia ramosissima is often confused with the more widespread L. texana; it can be distinguished by its thinner, more intricately branched stems, 5-7 florets per head, sulcate cypselae, and later daily flowering time (A. S. Tomb 1980).