Vascular Plants of Williamson County

Allium ampeloprasum [Alliaceae]
wild leek

Allium ampeloprasum L., wild leek. Perennial herb, clonal, geophytic, bulb–bearing, fibrous–rooted, initially rosetted, 1—several–stemmed at base, smaller bulbs often attached, with 1 erect inflorescence per shoot, ascending to suberect, with inflorescence in range to 125 cm tall; shoots with to 11 spreading, aboveground leaves to midplant, leaves only basal with long sheaths attached at base of bulb, with several green and photosynthetic leaves at flowering but withering from leaf tip backward, glabrous and somewhat glaucous, having strong odor of onion–garlic; bulb ovoid, when fully developed to 50 × 45 mm, white, bulb scales fleshy having many parallel veins and lacking netlike cell patterns between principal veins, cells vertically elongate with straight walls (rectangular); sister bulbs (increase bulbs) several often present at base of bulb, acuminate–ovate in outline and compressed; bulblets on bulb, ovoid, ca. 10 mm diameter, tan, hard, with 1 flat face and pointed at tip; adventitious roots many from flat stem at base of bulb.

Stem

Stem ± cylindric, to 8 mm diameter at top of bulb, white where covered by leaf sheaths, green above the uppermost leaf sheath; solid.

Leaves

Leaves alternate distichous, simple and sheathing; sheath closed, cylindric to low–ridged, to 600 mm long increasing from the lowest to uppermost leaf, to midplant and hiding peduncle (scape), with membranous, ligulelike extension 2—3 mm above base of blade, persistent; blade long–tapered lanceolate–linear, 300—500 × < 15—36 mm, papillate–ciliate on margins, long–acuminate at tip, parallel–veined with midrib raised to keeled on lower surface.

Inflorescence

Inflorescence umbel–like, spheroid, in range 70—80 mm, 300—500–flowered, with old flowers and younger flowers mixed, flowers opening over several weeks for each inflorescence, bracteate, glabrous; bracts subtending umbel 2, covering flower buds when first formed, the lower bract encircling axis, to 100 mm long, triangular to below midpoint and with an abruptly tapered and linear upper portion, leaflike, separated from upper bract by internode of several mm, upper bract narrower and shorter, to 65 mm long and only half–encircling axis, often abscising after flowering; bractlet subtending pedicel present, membranous, long–acuminate triangular, to 6 mm long, aging scarious and wedged between pedicel bases; pedicels radiating from spheroidal center of inflorescence, at anthesis < 35—45 mm long, 0.5—0.7 mm diameter at midpoint, pink aging whitish, glabrous.

Flower

Flower bisexual, radial, 3 mm across, ovoid (urn–shaped); tepals 6 in 2 whorls, dimorphic, free, white at base to pink or pinkish above midpoint and having green midstripe from above base to tip; outer tepals ovate and cupped, ca. 5 × 2 mm, ± keeled, conspicuously papillate on surface, keel, and margins; inner tepals appressed to ovary, oblong–elliptic, ca. 5 × 1.5—1.7, faintly pink above midpoint, flatter and narrower > outer tepals, midvein raised to midpoint, with some papillae only on margins; stamens 6 in 2 whorls, dimorphic, whorl opposite outer tepals ± free, other whorl fused to bases of inner tepals, ca. 6 mm long at maturity (when exserted); filaments membranous, glabrous, of free stamens ovate to midpoint and threadlike above midpoint, of stamens opposite inner tepals 3–lobed to midpoint, central lobe somewhat cylindric gradually tapered to tip, lateral lobes (teeth) flattened and triangular in lower portion and threadlike above, subequal with filament of fertile stamen; anthers dorsifixed–versatile, dithecal, ± 1 mm long, pale yellow, arrow–shaped at base, longitudinally dehiscent; pollen pale yellow; nectary beneath ovary not producing nectar; pistil 1, ca. 6 mm long; ovary superior, low 6–lobed, ovoid but when pollen released elongating to 0.7 mm below an interrupted ledge, ca. 2.5 × 2.2—2.3 mm, green with whitish furrows, lobes without crest but papillate at top, 3–chambered, each chamber filled with 2 ovules attached to center; style arising from pit at top of ovary, when pollen released 4—4.5 mm long, pinkish to white, tapered to tip; stigma capitate, exserted at same level as anthers, not lobed.

Fruit

Fruit capsule, loculicidal, typically sterile with 6 aborted ovules, sterile fruit ± dehiscent, ± pyramidal and 3–sided, 3—3.5 mm long; hidden by persistent, papery tepals.

Seed

Seed not observed.

A. C. Gibson