Salsola kali



Salsola kali

L. 1753

pronounced: SAL-so-lah KAH-lee

(Amaranthaceae — the amaranth family)

subfamily: Chenopodoideae

synonym — Salsola tragus

L. 1756

pronounced: SAL-so-lah TRAY-ghuss

synonym — Salsola australis

R.Br. 1810

pronounced: SAL-so-lah oss-TRAH-liss

common names: roly-poly, prickly saltwort, buckbush, tumbleweed

Some systems of classification place this plant in the family Chenopodiaceae. I am following the Kew Plant List by placing it, and all other plants that were classed as Chenopodiaceae, in Amaranthacae.

Salsola is from the Latin salsa, salted things; most species in this genus have a high salt tolerance; kali is the Arabic name for the saltwort. The chemical term alkali is Arabic, ‘from kali’. The traditional source of alkali in western Europe, for the manufacture of glass, soap and other products, had been potash obtained from wood ash; but by the 18th century deforestation had rendered this uneconomical, and alkali had to be imported from North America, Scandinavia and Russia, where large forests still stood. Especially in Spain, where the saltwort plants were called barilla, a substantial local soda ash industry grew up using saltwort: Salsola kali contains up to 30% sodium carbonate. In Britain, the only local source of alkali was from kelp, which washed ashore in Scotland and Ireland. In 1783 King Louis XVI of France and the French Academy of Sciences offered a prize of 2,400 livres for a method to produce alkali from sea salt. In 1791 Nicolas Leblanc, physician to the Duke of Orléans, patented his process, which soon made the production from wood ash, saltwort and kelp redundant.

In the synonym, tragus is from the Greek τραγος (tragos), a he-goat, the name given to a small cartilaginous flap in front of the external opening of the human ear, tufted with hair in a man, and resembling a goat’s beard.
There is at present considerable confusion over the taxonomy of Salsola species not only within Australia, but also in other parts of the world. In Australia the plant is usually known as Salsola kali, while in America it is usually called Salsola tragus. Some consider S. kali and S. tragus to be separate species. Naturalized populations of both in North America and Australia are thought to have originated in Eurasia. However, early explorers reported Buckbush in the Australian outback, well before the European settlement of these regions. The plant is one of those collected in 1770 by Banks and Solander during the voyage of the Endeavour. It was collected at the Endeavour River (Cooktown).

Recent studies in Western Australia have suggested that some, if not all, of these inland populations are of Salsola australis, probably a truly native species.

This is the tumbleweed so often seen rolling down the streets of derelict towns of the Wild West in cowboy movies. It is an erect or rounded annual or biennial herbaceous shrub with hairless and somewhat succulent stems when fresh, and grows up to about a metre in height. When mature, the stems and leaves become brittle, and the bushes break off at ground level and are subject to rolling away by the wind, shedding fruits as they go, and often becoming entangled in other vegetation or in fences. The alternate leaves are without stalks, cylindrical, slender and stiff, 1 – 3 cm long and 2 – 3 mm wide. Flowers occur in the angles between stem and leaves and are subtended by rigid, sharply pointed, small bracts. The flowers are white with a tinge of green, insignificant and solitary. The pale green to creamy pink fruiting body is 5 – 9 mm in diameter, and consists of 5 wings. The plant can be found right along the Queensland coastal strip, except in the northern Cape York area, as well as in inland parts. In other Australian states, it is often found as a weed of cotton crops.

dangerous 2The plant is potentially toxic to livestock. They will eat it when it is young, but it becomes unpalatable as it matures. Horses will graze it only when very hungry, but sheep and cattle graze it quite readily, and can be poisoned with chronic kidney disease as oxalates from the plant build up in their bodies. Muscle tremors occur, followed by a staggering gait, collapse and rapid death. In the dry inland areas, it is an early colonizer after rain, and this is when it is a danger to hungry stock.


Photographs taken on Picnic Bay foreshore 2012, Cockle Bay 2014
Page last updated 27th March 2019