Thalictrum texanum

Roots becoming black when dry, tuberous, not ribbed, irregular. Stems erect, 10-45 cm, rigid, glabrous. Leaves: distal cauline long-petiolate. Leaf blade 2×-ternately compound; leaflets cuneate to reniform, undivided, cleft, or lobed, 2-7 mm wide, margins entire or sometimes weakly crenate, surfaces glabrous, somewhat glaucous. Inflorescences terminal, racemes, several flowered. Flowers: sepals lanceolate to obovate, in staminate flowers 1.7-3 mm, in pistillate flowers 0.7-1.5 mm; filaments colored, not white, ca. 1.5 mm; anthers 1.4-2 mm; stigma color unknown. Achenes few, not reflexed, nearly sessile; stipe 0.1-0.3 mm; body ovoid, not laterally compressed, adaxial surface 2.7-3.7 × 1.4-1.6 mm, glabrous, prominently 6-8-veined, veins not anastomosing-reticulate; beak 0.5-1 mm.

Flowering early spring (Mar-Apr). Margins or openings of mesic woodlands or forests; of conservation concern; 10-100 m; Tex.

Somewhat difficult to locate in the field, Thalictrum texanum is currently known from only two populations. It is closely related to T . arkansanum and T . debile and sometimes treated as a variety of the latter.

Thalictrum confine is quite similar to T . occidentale and T . venulosum ; it has been treated as a variety or synonym of the latter (R. S. Mitchell 1988).