Buffalo burr (pincushion nightshade)
Annual herb to c. 1 m high, green or grey-green, tomentose with stellate and minute glandular hairs; prickles abundant on most parts.
Leaves ± pinnatisect, ovate to ± oblong in outline, 2–10 cm long, 1–8 cm wide, lobed; lobes obovate, lower ones often forming leaflets, both surfaces greyish tomentose; petiole to 5 cm long.
Inflorescences few-10-flowered; peduncle 15–30 mm long; rachis to 60 mm long; pedicels 5–10 mm long. Calyx 6–10 mm long, enlarged in fruit; lobes 3–5 mm long. Corolla irregularly rotate, 30–40 mm diam., bright yellow. Anthers unequal, 4 anthers straight, other anther curved.
Berry c. 10 mm diam., drying blackish, skin papery.