Difference between revisions of "Lilium grayi"

Latest revision as of 21:14, 5 November 2020

Copyright: Flora of North America Association

Bulbs often yellowish, rhizomatous, unbranched, 2.2–2.6 × 3.8–5 cm, 0.5–0.6 times taller than long, 2 years’ growth evident as annual bulbs, scaleless sections between these 1.2–2.5 cm; scales 1–2-segmented, longest 0.9–2.2 cm; stem roots present. Stems to 1.3 m. Buds rounded in cross section. Leaves in 3–5 whorls or partial whorls, 3–12 leaves per whorl, ± horizontal to occasionally slightly ascending, drooping at tips, 4.1–12.7 × 1.5–3.6 cm, 1.9–5 times longer than wide; blade elliptic, occasionally narrowly so or barely lanceolate, margins not undulate, apex acute, usually barely acuminate in distal leaves; principal veins impressed adaxially, veins and margins noticeably roughened abaxially with tiny ± deltoid epidermal spicules, especially apically and on proximal leaves. Inflorescences racemose, 1–9(–16)-flowered. Flowers nodding, not fragrant; perianth campanulate; sepals and petals barely recurved 2/3–9/10 along length from base, yellow-orange proximally, pale red distally, spotted maroon, pale red or sometimes red-orange abaxially, not distinctly clawed; sepals not ridged abaxially, 3.2–5.6 × 1.3–2 cm; petals 3.1–5.5 × 1.2–2 cm; stamens included; filaments ± parallel to style, barely spreading, diverging 3°–9° from axis, red; anthers magenta, 0.4–1.2 cm; pollen brown-rust; pistil 2.4–3.8 cm; ovary 0.8–1.7 cm; style red; pedicel 2.6–6.5 cm. Capsules 2.1–3.7 × 1.5–2.1 cm, 1.5–2.1 times longer than wide. Seeds not counted. 2n = 24.

Phenology: Flowering summer (late Jun–mid Jul).
Habitat: Grassy balds, openings in red spruce (Picea rubens Sargent)–Fraser fir (Abies fraseri (Pursh) Poiret) forests, moist hardwood bogs, seeps, and meadows at lower elevations
Elevation: 1200–1900 m

N.C., Tenn., Va.

Discussion

The narrowly endemic Gray’s lily blooms predictably on or about July 4 in the balds and forest openings of the Roan Mountain massif shared by North Carolina and Tennessee. In its unadulterated form it also occupies the higher elevations of the Blue Ridge Mountains, including Grandfather Mountain in North Carolina and Mount Rogers and Whitetop Mountain in Virginia. A few populations occur at lower elevations (below 900 m) in streamside meadows along the Blue Ridge Parkway in northern North Carolina (Alleghany County), but in similar settings farther north in Virginia introgression with L. canadense occurs.

Lilium ×pseudograyi Grove (as species) is a name given to frequent hybrids between L. grayi and L. canadense that are scattered at somewhat lower elevations (usually 700–1000 m) in the southern Appalachians. The generally small stature of these hybrids is misleading and encourages the label of bona fide L. grayi, but in most respects they are intermediate. Sepal lengths of 4.8–6.2 cm and floral tube lengths of 3.2–4 cm predominate, and these are between the ranges of the two parent species. The freshwater wetland or moist hardwood habitat of these hybrids also reveals the contribution of L. canadense to their genome.

J. K. Small (1933) made reference to depredations by lily enthusiasts who sought Gray’s lily because of its supposed rarity, and this continues today, though to a lesser degree. Of greater threat, perhaps, is succession on the high grassy balds that gradually shades and crowds the plants; like most lilies, this one requires open conditions for vigor and reproduction.

Although fritillaries (Speyeria spp., family Nymphalidae) pilfer nectar from flowers of Gray’s lily, ruby-throated hummingbirds [Archilochus colubris (Linnaeus), family Trochilidae] are its only reliable pollinator. This red, tubular-flowered lily represents the zenith of pollinator-mediated evolution in the eastern true lilies, and is a high-elevation derivative of the ancestral stock that also produced Lilium canadense. The level of floral convergence with independently derived western Lilium species such as L. bolanderi and L. maritimum is remarkable and must be due to selection pressures exerted by hummingbirds during the floral evolution of these species.

Selected References

None.

Lower Taxa