FABACEAE: Legume Family
KEY TO SPECIES OF LUPINUS
1. Plants with a distinct solitary prominent erect or nearly so main stem with spreading to ascending or nearly straight divergent branches at ca 45 °, the larger branches perennial; stipules absent or fused to petiole (1)2-4 mm, a free filamentous portion 0-19 mm ................................................... 2
2. Stipules including fused portion usually not evident, free portion absent or uncommonly very short, often evident as a tuft of hairs. Petiole to 55 mm, hairs 0.5-1(1.5) mm. Most fruits 15-25 mm, apex pointed at end of upper edge ........................................... L. westianus
2. Stipules conspicuous, on most leaves each with a free portion to 19 mm. Most petioles to 35 mm, hairs ca 1-1.7 mm. Most fruits 27-38 mm, point of apex ca midway to slightly below upper edge ......................... L. cumulicola
1. Plants with little or no distinct erect main stem, branches arising at or near ground surface, spreading and trailing or ascending, at least some branches biennial, occasionally some living 3 years, and rarely some 4 or more; stipules present and fused to petiole 3-32 mm with a free filamentous portion 4-60(146) mm ............................................................................... 3
3. Year 1 stems and petioles with shaggy long hairs; free portion of stipules 18-60(146) mm; standard petal with a vivid or pale red to purple-maroon eyespot ............................................................... L. villosus
3. Year 1 stems and petioles with dense somewhat smoothly arranged hairs; free portion of stipules 5-25 mm; standard petal with a white or cream eyespot ............................................................... L. diffusus