Allium stellatum  Nutt. ex Ker Gawl.

Wild Onion

Allium stellatum plant2

Family - Liliaceae

Habit - Perennial forb from a bulb.

Allium stellatum baseBase of plant.

Allium stellatum bulb2Bulbs.

Stems - Bulbs to 4 cm, with a papery outer coating and slightly thickened roots. Aerial stems to 60 cm tall, erect, terete, glabrous, sometimes glaucous, bent at the apex when immature, becoming erect with age, green.

Allium stellatum stemPortion of stem and persistent, flat leaf blade.

Leaves - Basal or nearly so, to 40 cm long, 5 mm broad or less, flattened, linear, present during anthesis, light green.

Inflorescence - Terminal umbel with numerous flowers, nodding when immature. Bulblets absent. Pedicels much longer than the flowers, glabrous, purplish in strong sun, to 2 cm long.

Allium stellatum inflorescence3Inflorescence.

Allium stellatum inflorescence
These views illustrate the hooked peduncle of an immature inflorescence.

Flowers - Perianth pink, widely spreading, 6-parted, the tepals to 7 mm long, elliptic, typically acute at the apex, glabrous. Stamens 6, erect, exserted beyond the perianth parts. Filaments terete, pink, glabrous. Anthers yellow when fresh, quickly becoming brown. Style pink, terete, glabrous, shorter than or equaling the stamens.

Allium stellatum inflorescence2Flowers.

Allium stellatum flower

Allium stellatum flower2

Fruits - Capsules 3-5 mm long, obovoid, 3-lobed, each lobe with a pair of hornlike, triangular projections near the top. Seeds black.

Allium stellatum seedsPartially dehisced fruits.

Flowering - July - November.

Habitat - Glades, bluffs, open dry woods, roadsides.

Origin - Native to U.S.

Other info. - This showy species is reasonably common in Missouri glades south of the Missouri River. It is the latest blooming onion in Missouri and is easy to identify in the field. The papery-covered bulb, pink flowers, and flat, persistent leaves are good characters to look for. Note that A. stellatum can sometimes be confused with the closely related A. cernuum Roth, which looks similar. The latter species has nodding inflorescences (cernuum means "nodding"), but A. stellatum does this as well when not fully mature. The inflorescence of A. stellatum becomes erect with time. A more reliable difference between the two plants is the flower shape. A. stellatum has a spreading and open perianth, whereas the perianth of A. cernuum is campanulate (bell-shaped).

The natural range of this species is peculiar, apparently comprising two disjunct populations. It is found in Missouri and adjoining states, and separately in the north-central U.S. and into Canada.

Photographs taken in Eminence, MO., 9-21-03 (DETenaglia); also at Shaw Nature Reserve, Franklin County, MO, 8-19-2007; Taum Sauk State Park, Iron County, MO, 7-18-2011; Ha Ha Tonka State Park, Camden County, MO, 9-2-2012; and Victoria Glade, Jefferson County, MO, 9-7-2014 (SRTurner).


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