Flora of North America species comparison

Hybrids between Delphinium cardinale and D. parryi have been named D. ×inflexum Davidson. Because of horticultural interest in red-flowered delphiniums, garden hybrids have been made with D. elatum, D. hesperium, D. hutchinsoniae, D. nudicaule, D. parishii, D. penardii, D. scopulorum, D. tatsienense Franchet, D. uliginosum, and D. zalil Aitchison & Hemsley, although D. cardinale does not grow with any of these in the wild.

Plants of Delphinium cardinale are quite variable in size, leaf distribution, and pubescence, resulting in considerable differences between, and sometimes within, populations. No patterns could be seen, however, to justify recognition of separate taxa within D. cardinale. Populations farther south (in Baja California, Mexico) may represent a distinct entity; they require further study.

The only possible confusion between Delphinium cardinale (seeds not ringed, fruits erect, grows in relatively dry sites) and another taxon might occur with Delphinium nudicaule (seeds ringed, fruits spreading, grows in moist habitats). The two are separated geographically and phenologically (although D. cardinale may begin flowering in southern California before D. nudicaule has finished in northern California).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Subspecies 2 (2 in the flora).

Although Delphinium menziesii has often been confused with D. nuttallii, it may be distinguished by its consistently larger flowers and usually fewer flowers per plant. Interestingly, each species produces both blue-purple and yellowish flower colors in separate populations.

The Chehalis consider Delphinium menziesii poisonous, but they also apply it to sores. The women of the Thompson Indians use it as a love charm (D. E. Moerman 1986, subspecies not indicated).

(Discussion copyrighted by Flora of North America; reprinted with permission.)