Colorado Paperflower

Psilostrophe bakeri is a biennial or perennial herb that rarely flowers during its first year. It usually grows 5–12 cm (2.0–4.7 in) tall, though it may exceed 20 cm (7.9 in). Its stems are gray to gray-green and covered with cobwebby hairs. The flower heads are arranged in loose, flat-topped clusters on stalks generally 15–35 mm (0.59–1.38 in) long. Each head usually has four or five yellow ray florets, occasionally as many as eight, surrounding 10–20 disc florets. The fruits are cypselae, usually hairless and sometimes dotted with glands, with a pappus of four or five oblong scales. Its chromosome number is 2n = 32.

The species is native to Colorado and Idaho. It grows on rocky, often alkaline slopes and knolls at elevations of 1,300–2,000 m (4,300–6,600 ft). Flowering occurs in May and June. An annotated checklist for Colorado National Monument records the species as present, regionally endemic, and rare within the monument.

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