Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.

Key to Chenopodium

Chenopodiaceae

Chenopodium

Copy permalink to share

1 Seeds arranged vertically or both horizontally and vertically in the fruit; leaf blades glabrous or occasionally sparsely farinose.
  2 Perianth segments 5; plants perennial; [Blitum, sect. Blitum]
  2 Perianth segments 3; plants annual.
    3 Leaves lanceolate or oblong, glaucous on the lower surface; [Oxybasis, sect. Pseudoblitum]
    3 Leaves triangular or rhombic, green or white-farinose on the lower surface.
      4 Leaves farinose on the lower surface; [Oxybasis, sect. Oxybasis]
      4 Leaves glabrous and green on the lower surface.
        5 Glomerules 3-10 mm in diameter, borne sessile on unbranched terminal and occasionally axillary spikes; perianth segments fleshy and red at maturity; [Blitum, sect. Blitum]
        5 Glomerules 2-5 mm in diameter, borne sessile on lateral branched spikes; perianth segments membranaceous, green at maturity; [Oxybasis, sect. Pseudoblitum]
1 Seeds arranged horizontally in the fruit; leaf blades usually farinose.
          6 Flowers individually disposed in panicles; leaf blades glabrous; [Chenopodiastrum, sect. Grossefoveata]
          6 Flowers in loose or dense glomerules; leaf blades usually farinose; [subgenus Chenopodium, section Chenopodium].
             7 Primary leaves linear, linear-lanceolate, at least 2-3× as long as wide, usually untoothed and unlobed (but often with 2 basal lobes in C. foggii); [subsection Leptophylla].
                 9 Seeds 0.9-1.1 mm in diameter; taller plants often < 4 dm tall
                 9 Seeds 1.4-1.6 mm in diameter; taller plants > 4 dm tall
                   10 Leaves > 3× as long as wide.
                     11 Perianth spreading from fruit at maturity; plants strictly erect
                     11 Perianth enclosing the fruit at maturity; plants erect to spreading.
             7 Primary leaves ovate, rhombic, triangular, or lanceolate, usually with basal lobes and often also with additional teeth on the margins.
                          13 Seeds honeycomb-pitted; [subsection Favosa].
                              15 Style bases without yellow area; seeds 1.3-2.0 mm in diameter.
                                               23 Seeds 1.0-1.5 mm in diameter, the seed margin sharp; leaf blades without basal lobes; [Chenopodiastrum, sect. Chenopodiastrum]
                                               23 Seeds 0.8-1.2 mm in diameter, the seed margin rounded; leaf blades often with basal lobes; [Oxybasis, sect. Urbica]
                                                    25 Leaves not aromatic; flowers in each glomerule in markedly different stages of development; [subsection Standleyana]
                                                    25 Leaves strongly malodorous; flowers in each glomerule in similar stages of development; [subsection Chenopodium]