Tetradymia axillaris

A. Nelson

Bot. Gaz. 37: 277. 1904.

Treatment appears in FNA Volume 20. Treatment on page 632. Mentioned on page 630.

Shrubs, 50–150 cm. Stems 1–5+, erect or spreading, spiny, evenly pannose. Leaves: primaries forming straight, ± squarrose spines, 10–50 mm; secondaries filiform to clavate, 2–12(–20) mm, sparsely arachnose or glabrous. Heads 1–3 (in axils of spines). Peduncles 4–15 mm. Involucres turbinate to campanulate, 7–9 mm. Phyllaries 5, ovate. Florets 5–7; corollas pale yellow, 7.5–9 mm. Cypselae 4.5–5.5 mm, densely pilose (hairs 6–14 mm); pappi of ca. 25, subulate to setiform scales 6–7.5 mm.


Varieties 2 (2 in the flora).

The two varieties of Tetradymia axillaris are partially sympatric and intergrade in areas of overlap.

Selected References



1 Peduncles and phyllaries pannose to tomentose; hairs of cypselae 9–14 mm Tetradymia axillaris var. longispina
1 Peduncles and phyllaries glabrous; hairs of cypselae 6–8(–10) mm Tetradymia axillaris var. axillaris