White Flowered Forbs

White Flowered Forbs
African rue
Broadleaved pepperweed
Field bindweed
Hary whitetop
Horehound
Lens-podded hoarycress
Onionweed
Oxeye daisy
Poison hemlock
White clover
White sweetclover
Whitetop

 

Onionweed
Cardaria chalepensis (L.) Hand.-Maz. (Mustard family, Brassicaceae)
 

Description

Onionweed is a tufted, dark green annual or short-lived perennial monocot herb with hollow stem up to 27-1/2 inches tall. The root system has a series of tuberlike parts at the base of the stem.

Leaves: Leaves are basal; the plant takes the form of a large tuft of onionlike rounded or slightly flattened hollow leaves, 4 to 12 inches long; 3/16 inch in diameter; glabrous except on margins.

Flowers: Flowers February to May; the flowering inflorescence is a simple raceme or open panicle, 5-7/8 to 27-1/2 inches long, with widely spaced flowers; 3/16 to 1/2 inch wide with 6 tepals (petals and sepals) which are generally white or very pale pink with a neat central longitudinal stripe of brown to reddish-purple; flowers are diurnal, closing at night and in overcast or low light weather conditions.

Fruit: The fruit is a rounded capsule, 3/16 to 1/4 inch long, containing 6 seeds.

Habitat

Dry sandy or rocky disturbed sites such as waste places, pastures, and along roadsides and railroad rights-of-way within elevations that generally range below 4,600 feet.

Propagation/Phenology

Reproduces by seed.

Comments

Native to Eurasia and North Africa; onionweed seeds prolifically and can establish large populations quickly and is drought resistant. Onionweed could be confused with some native onions (Allium L.); Federal (U.S.) noxious weed.

Collage of images of Onionweed

 
Forest Service Shield
Invasive plants and weeds of the national forests and grasslands in the southwestern region
Onionweed plants Onionweed flowering inflorescence Onionweed flowering inflorescence