Similar to S. idahoense but more slender, with pale green to glaucous stems and leaves. Stems branched, narrowly winged. Leaves firm textured, to 3mm wide, shorter than stems. Spathes two, pale green or purple flushed. Flowers violet-blue, up to 1.8cm in diameter, early to late summer. Eastern North America from Nova Scotia to Florida and Mississippi, in damp to dry grassland, marshes and open woodland.