Alternanthera caracasana, Khaki Weed, Southwest Desert Flora

Alternanthera caracasana, Khaki Weed

1 Khaki Weed has whitish, yellowish or straw colored flowers surrounded by white bracts. Flowers are mostly inconspicuous but visible with naked eye. The fruits are one seeded utricles. Alternanthera caracasana

3 Khaki Weed has shiny bright green leaves emerging from opposite sides of stems. Note the leaves are oval or obovate with short sharp flexible points. The leaves are of unequal size throughout, have petioles clasping to the stems. Alternanthera caracasana

3 Khaki Weed is also called Mat Chaff-flower and Washerwoman. These plants have been introduced from Central and South America. Plants are perennial and may grow up to 3 feet. Note the ability to form mats spreading along the ground. Alternanthera caracasana

Scientific Name: Alternanthera caracasana
Common Name: Khaki Weed

Also Called: Mat Chaff-flower, Washerwoman

Family: Amaranthaceae, Pigweed Family

Synonyms: (Achyranthes peploides, Achyranthes repens, Alternanthera peploides, Alternanthera pungens, Alternanthera repens)

Status: Introduced: Native to Central and South America.

Duration: Perennial

Size: Up to 3 feet.

Growth Form: Forb/herb; heavily stemmed, woody root, spreading along the ground (procumbent), forming mats.

Leaves: Bright green; opposite, glabrous, leaves variable, oval or obovate with short sharp flexible point, paired leaves of unequal size throughout, petioles, clasping.

Flower Color: Whitish, yellowish or straw colored, mostly inconspicuous; sepals only, lanceolate, sharp pointed, sessile in axillary spikes, flowers surrounded by conspicuous white bracts; fruit is a one seeded utricle.

Flowering Season: August to October.

Elevation: sea level to 6,000 feet.

Habitat Preferences: Gravel, sand bars, sidewalks; 0-2000 m; Generally waste places.

Recorded Range: Khaki Weed is an introduced species found in the southern part of the United States in; AL, AR, AZ, CA, FL, GA, HI, LA, MD, MO, MS, NC, NM, OK, SC and TX. It is also introduced in Baja California and northern and central Mexico and Hawaii. It is native to Puerto Rico, the Virgin Islands and Central and South America.

North America & US County Distribution Map for Alternanthera caracasana.

U.S. Weed Information: No data available.

Invasive/Noxious Weed Information: In North America, the genus Alternanthera is listed as a Noxious Weed by the state of Arkansas. Plants included here are invasive or noxious.

Wetland Indicator: No data available.
Threatened/Endangered Information: No data available.

Genus Information: In North America there are 129 species and 200 accepted taxa overall for Alternanthera. World wide, The Plant List includes 552 accepted species names with 963 infraspecific rank for the genus.

In the Southwestern United States, Arizona has 3 species of Alternanthera, California has 1 species, Nevada has 0 species, New Mexico has 1 species, Texas has 7 species and Utah has 0 species. All data is approximate and subject to taxonomic changes.

Comments: Khaki Weed is low growing, mat forming resilient species with whitish flowers and conspicuous white bracts tightly tucked in among leaf axil. It is distinctive and conspicuous, almost striking with its bright green leaves of varying shape and size. It is generally listed as a weed, a noxious weed in Arkansas, often found growing in disturbed areas and a variety of habitats.

In Southwest Desert Flora also see a closely related species also called "Khakiweed", Alternathera pungens with which is it often confused.

Khaki Weed is similar is appearance and habitat to another member of the Amaranth family, Small Matweed, Guilleminea densa, also an Amaranth found in Arizona.

Etymology: The genus "Alternanthera" comes from the Latin alternus, "alternate", and the Greek anthera "anther", referring to the stamens and anthers which are alternately fertile and barren (sterile). The species epithet "caracasana" comes from the Caracas region of Venezuela, where it is native.

Ethnobotany From A Zapotec Natural History, Part 2, (University of Washington,) "Alternanthera caracasana is a low growing herb from creeping underground stem; tiny flowers; literally “diarrhea plant”; medicine for diarrhea, taken in water at room temperature; medicine is “fresca”; also used to treat `fright´ ; also for decoration; animals eat it."

Additionally, parts supposedly have been used by the people of Chinchero, Peru as a tea during childbirth.