Flora of North America species comparison

The author citations often seen for this species derive from Baker (1874), who published the name as Lilium columbianum “Hanson in hort., Leichtlin”; this authority is given by various later writers as Hanson, or Baker, or Hanson ex Baker. However, Ducharte’s (1871) recapitulation of a letter from M. Leichtlin is apparently the first confirmed and valid publication of L. columbianum, and hence that citation is used here.

This widespread lily is rather variable. In California plants the stamens are considerably less exserted than those of plants found farther north. Lilium columbianum may intergrade with L. kelloggii along Highway 199 at the border between California and Oregon; these plants are slightly fragrant, the stamens moderately exserted, and the bulb scales unsegmented. Lilium columbianum hybridizes with L. pardalinum subspp. wigginsii and vollmeri, and extensively with L. occidentale in Oregon.

Lilium columbianum is pollinated primarily by rufous hummingbirds [Selasphorus rufus (J. F. Gmelin), family Trochilidae] and to a lesser extent by large butterflies, including the pale swallowtail (Papilio eurymedon Lucas, family Papilionidae).

Native Americans used Lilium columbianum bulbs as a food or peppery condiment, sometimes mixed with meat or salmon roe. For many, it was a staple food (J. Pojar and A. MacKinnon 1994).

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

The largest Lilium east of the Rocky Mountains and the commonest over most of its range, the Turk’s-cap lily is a familiar sight throughout much of the southern Appalachians and along the northern Atlantic coastal plain. Flowers are rather variable; those in the north are sometimes floridly colored with dark purple bases on the perianth parts. The single report from Vermont (F. C. Seymour 1993) remains unconfirmed; however, recent collections from Washington Parish in Louisiana, Perry County in Missouri, and Bamberg County in the coastal plain of South Carolina extend the range of this species.

Lilium superbum shares distinctive features with L. michauxii, L. pyrophilum, and L. iridollae that indicate a close relationship and are diagnostically useful, namely paired ridges on the backs of the sepals and buds that are triangular in cross section. None has the red style characteristic of the other eastern pendent lily clade (L. michiganense, L. canadense, and L. grayi) centered to the northwest, and only L. iridollae sometimes has the leaf margins and veins roughened abaxially as is characteristic of L. canadense and its close relatives.

Common inheritance of a suite of unique, derived features and peripheral allopatric distributions suggest that Lilium pyrophilum and L. iridollae may be geographical isolates of broadly distributed L. superbum ancestral stock; both restricted species occur in specialized wetland habitats. Geography aside, the three are unequivocally distinguished only by various combinations of leaf and bulb characteristics, flower color, habitat, and blooming time. However, the overall degree of separation is comparable to that between many other species in the genus. Lilium superbum blooms the earliest, is the largest, and has the most numerous and largest flowers, and the long, narrow leaves in many whorls are distinctive. Lilium michauxii overlaps in range with these three species but is easily separated morphologically and ecologically.

Lilium superbum is pollinated primarily by the swallowtail butterflies that are common within its range, among them the spicebush (Papilio troilus Linnaeus, family Papilionidae), pipevine (Battus philenor Linnaeus), and eastern tiger (Papilio glaucus Linnaeus). Great spangled fritillaries [Speyeria cybele (Fabricius), family Nymphalidae] also visit the Turk’s-cap lily (R. M. Adams and W. J. Dress 1982).

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