| Carex oligosperma Michx. | |
| Publ. & Syn. | Carex physocarpa C. Presl, Reliq. Haenk. 1: 205 (1828). Type: Nootka Sound (British Columbia, Canada) or Port Mulgrave (Alaska), leg. Haenke. |
| Notes | Elven and Wischmann: The three species Carex livida, C. panicea, and C. vaginata differ in numerous characters but hybridize freely nearly everywhere they meet in northern Europe. Some morphological intermediates have aborting or reduced anthers but plants with intermediate morphological features are often found with fully developed anthers and pollen. Plants with intermediate traits constitute up to 20-30% of the material from some regions (Wischmann and Elven 2008) and introgression is suggested. The fourth northern species assigned to this section, C. laxa, does not seem to partake in hybridization. |
| Chromosomes | 76. - Canada (Manitoba, Quebec). - Löve and Löve (1981d, 1982c). |
| Geography | American Beringian & North American (NE): CAN. |
| Distribution | N = S E = R HL = r [ key ] |
| Parent taxon | Carex L. |
| PAF ID | 3309012 |