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Asphodelus fistulosus - onionweed

Scientific Family
Asphodelaceae
Synonyms
Asphodelus tenuifolius
Other common names
pink asphodel
onion asphodel
hollow-stem asphodel
wild onion
Plant type
Forbs and Subshrubs
Origin
Introduced
Lifecycle
Annual
Biennial or perennial
Similar species
Asphodelus ayardii
Height
To nearly 2-1/3 feet
Riparian
No

Annual, biennial or perennial with hollow, upright, leafless stems; clumps of many grass-like leaves grow from the plant base. White to pale pink flowers with brown or reddish center stripes grow on spike-like clusters.

Herb, annual or perennial or biennial, from swollen rhizomes; leaves numerous, basal, blade narrow; stems hollow; sepals similar shapes, barely fused, prominently veined; stamens 6, filaments base expanded; style 1, weakly 3-branched; ovary 3-chambered.

Habitat

Found in dry, sandy and rocky places as well as pastures, open woodlands, rangelands, roadsides, railway lines, fields and waste places.

Plant Community
Desert Scrub
Disturbed Areas
Grasslands
Interior Chaparral
Pinyon Juniper Woodlands
Low elevation
0
High elevation
4600

Flower Characteristics

Each flower is about 3/4 inch across and has 6 white to pale pink tepals (sepals and petals). Each tepal has a brown or reddish stripe down its center. Up to 30 of these flowers are widely spaced along the upper parts of the branched flowering stem.

Flower color
White to pale pink
Flower shape
Regular
Tubular
No
First bloom month
March
Last bloom month
July
Flower clusters
Elongated

Leaf and Stem Characteristics

Leaves are grass-like, a bit fleshy, smooth, hollow and rounded or slightly flattened on their upper surface. Leaves grow to nearly 14 inches long and from 1/16 to 1/4 inch wide. Hollow stems are rigid, smooth and usually branched in their upper parts.

Leaf type
Simple
Leaf color
Dark green
Leaf shape
Narrow
Leaf margin
Smooth
Leaf attachment
Basal
Leaves clasp
No
Leaf hairs
None
Spines
No

Fruit and Seed Characteristics

Each fruit is a brown, rounded capsule, 1/4 to 1/2 inch long, with a wrinkled surface (rugose) and divided into 3 segments (chambers) each containing 1 to 2 seeds. Fruits turn from greenish to reddish-brown to brown as they mature.

Fruit type
Capsule
Fruit color
Brown

The seeds remain viable for several years and are easily transported in trade, on vehicles and by animals. Each seed is triangular, dark brown or black, 1/8 to 1/4 inch long and marked by deep depressions (pits) making for a rough surface texture.