All Floras      Advanced Search
FNA Vol. 21 Page 77, 78, 80, 81 Login | eFloras Home | Help
FNA | Family List | FNA Vol. 21 | Asteraceae | Silphium

7. Silphium integrifolium Michaux, Fl. Bor.-Amer. 2: 146. 1803.

Wholeleaf rosinweed

Plants caulescent, 40–200 cm; fibrous rooted. Stems terete to slightly square, sparsely scabrous or glabrous (sometimes glaucous). Leaves: basal caducous; cauline opposite, sessile; blades lanceolate to ovate, 2–23 × 0.1–11 cm, bases round to caudate, margins finely serrate or entire, apices acute to acuminate, faces hispid, scabrous, or glabrous. Phyllaries 17–37 in 2–3 series, outer appressed, apices acute to acuminate, abaxial faces glabrous, hispid, pilose, or scabrous, sometimes stipitate-glandular. Ray florets 12–36; corollas yellow. Disc florets 70–225; corollas yellow. Cypselae 9–14 × 6–10 mm; pappi 1–4 mm.

Varieties 2 (2 in flora): e North America.


1 Phyllaries: abaxial faces usually hispid, pilose, or scabrous, rarely glabrous; ray florets 12–22   7a Silphium integrifolium var. integrifolium
+ Phyllaries: abaxial faces glabrous; ray florets 20–36+   7b Silphium integrifolium var. laeve


 

Related Objects  
  • Distribution Map
  • Map

     |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |