Lilium stewartianum
Franchet (1892)
(Syn. Lilium habaense F.T. Wang & Tang, 1892; L. xanthellum F.T. Wang & Tang, 1933)
(Stewart’s Lily / 史都華百合 Shǐdūhuá Bǎihé)
Overview
Section: Sinomartagon (Asiatic section)
Origin: Western China (Yunnan and Sichuan provinces; Haba Snow Mountains, Dali–Lijiang region)
Habitat: Alpine and subalpine meadows, open rocky slopes, and shrubby grasslands, typically 3 000–4 400 m elevation
Type: High-altitude Asiatic lily, part of the cold-adapted Hengduan Mountains complex
Status: Regionally uncommon but locally frequent; range overlaps with L. taliense and L. nanum
Description
Lilium stewartianum is a slender, erect lily ranging from 40 – 70 cm tall. The bulb is ovoid, 2–3 cm in diameter, with 20–30 fleshy, white to pinkish scales.
Leaves are narrow, linear-lanceolate, 5–10 cm long × 2–5 mm wide, usually scattered or in irregular whorls along the stem.
The flowers (1 – 4 per stem) are nodding and campanulate, appearing in late June through August. Tepals are bright yellow to greenish-yellow with dense purplish or chestnut-brown spots, narrowly elliptic (3 – 4 cm × 0.6 – 1 cm), and curve backward at maturity. Nectaries are smooth to slightly papillose; filaments slender (1 – 1.5 cm), anthers yellow-orange; style 2 – 2.5 cm with capitate stigma, slight to no fragrance
Ecology
The species grows in alpine limestone meadows and open screes in the Hengduan range, often alongside dwarf rhododendrons, gentians, and sedges.
Conditions are harsh: strong sun, rapid drainage, snow cover in winter, and a growing season of only 8–10 weeks.
Adaptations include:
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compact growth habit and narrow leaves to reduce moisture loss;
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thick fleshy bulb scales for rapid energy mobilization;
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short flowering window synchronized with alpine pollinators (bees and hoverflies).
Populations formerly described as L. habaense occur at higher elevations (Haba Snow Mountain, 3 800 – 4 400 m), while L. xanthellum represents slightly lower, yellower-flowered forms.
Taxonomy & Relationships
Originally described by Franchet (1892), L. stewartianum became the focus of later taxonomic fragmentation, producing L. habaense and L. xanthellum as segregates.
However, Gao et al. (2015) demonstrated continuous morphological variation among these populations, arguing for a single polymorphic species.
This revision unified all three taxa under L. stewartianum (sensu lato), now encompassing a wide range of alpine morphotypes.
Genetics & Phylogeny
Cytology: 2n = 24 (diploid).
No complete plastome sequence has yet been published specifically for L. stewartianum, but ITS + cp-marker datasets (Du et al. 2017; Duan et al. 2022) place it securely within the western high-altitude Sinomartagon clade, near L. taliense, L. nanum, and L. fargesii.
Composite Phylogenetic Topology
┌── L. xanthellum (lower-elevation yellow form)
┌───────────┤
│ └── L. habaense (high alpine variant; Haba Mtn.)
Section │
Sinomartagon ───────┤
│ ├── L. stewartianum (typical form; mid-elevation)
│ └── L. taliense / L. nanum (sister lineages)
└── Lower-altitude Asiatic lilies (brownii, lancifolium, etc.)
This topology reflects a single adaptive radiation across elevational gradients in western Yunnan and Sichuan.
All members share small, nodding flowers, yellow-green hues, and cold-tolerant physiology, forming an ecologically cohesive alpine subgroup.
Cultivation
L. stewartianum and its variants are among the most challenging Asiatic lilies to cultivate:
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Soil: gritty limestone scree or alpine tufa, sharply drained
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Water: frequent light moisture in growth period, dry dormancy
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Temperature: requires winter freeze (–5 °C to –10 °C) and cool summers (< 20 °C)
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Light: full sun at high elevation or cool bright shade in lowland alpine houses
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Propagation: scaling or seed; germination slow, delayed hypogeal (may take 3 – 5 years to flower)
Bulbs rot easily under warm, stagnant, or humid conditions, a constant challenge in cultivation outside native alpine climates.
Evolutionary Context
Lilium stewartianum represents the westernmost alpine radiation of Sinomartagon, adapted to the glacial and periglacial landscapes of the Hengduan–Haba region.
The unification of habaense and xanthellum under stewartianum reflects the reality of cline-based speciation, where altitude and microclimate drive gradual morphological change rather than distinct genetic breaks.
This lineage links the low-elevation yellow Asiatic lilies (e.g., L. concolor, L. callosum) with the high-mountain dwarfs (L. nanum, L. lophophorum), bridging color and form transitions within the genus.
Works Cited
Franchet, A. “Plantae Davidianae Exsiccatae: Notes sur les Liliacées de la Chine.” Journal de Botanique 6 (1892): 177–182.
Wang, F.T., and Tang, T. “Notes on Chinese Lilies.” Acta Phytotaxonomica Sinica 10 (1933): 233–237.
Gao, Yun-Dong, et al. “Continuous Variation Supports Accommodating Lilium habaense and L. xanthellum within L. stewartianum (Liliaceae).” Phytotaxa 226 (2) (2015): 189–198. https://doi.org/10.11646/phytotaxa.226.2.10
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Du, Yun-Peng, et al. “Complete Chloroplast Genome Sequences of Lilium: Insights into Evolutionary Dynamics and Phylogenetic Analyses.” Scientific Reports 7 (2017): 5751.
Duan, Yong-Ping, et al. “Molecular Phylogeny and Biogeography of Lilium.” Botanical Journal of the Linnean Society 199 (3) (2022): 323–341.
Flora of China Vol. 24. “Lilium stewartianum.” Missouri Botanical Garden & Harvard University Herbaria, 2000.
BDLilies. “Lilium habaense (syn. stewartianum) — Yunnan Alpine Lily.” 2022. https://www.bdlilies.com/ls37.html
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Lilium TC. “Lilium habaense — Haba Mountain Lily.” 2023. https://www.lilium-tc.com
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