Source: California Invasive Plant Council

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Invasive Plants of California's Wildland

Bassia hyssopifolia
Scientific name   Bassia hyssopifolia
Additional name information:   (Pallas) Kuntze

Common name   bassia, five-hook bassia, thorn orache, five-horn smotherweed

Synonymous scientific names   Echinopsilon hyssopifolia, Salsola hyssopifolia

Closely related California natives   0

Closely related California non-natives:   0

Listed   CalEPPC List B,CDFA nl
By:   Guy Kyser,Marc C. Hoshovsky

Distinctive features:  

Bassia (Bassia hyssopifolia) is a grayish annual up to three and one third feet tall; with inconspicuous flowers and younger stems that are densely covered with long, soft, straight hairs. Branches angle out at thirty to sixty degrees from the stem. The small fruit has five distinctive hooked structures on each seed, looking and adhering like a five-legged tick. Overall, this plant looks similar to lambs' quarters (Chenopodium album), but it has smaller, elongated, pointed leaves. Bassia is sometimes confused with other members of the Chenopodiaceae, such as Russian thistle (Salsola tragus) or kochia (generally Kochia scoparia). Russian thistle is more profusely branched and spiny than bassia (Fischer et al. 1979). Bassia more closely resembles plants of the genus Kochia, within which some taxonomists believe it should be included (Hickman 1993). Bassia is hairier than kochia, produces a pronounced, woolly-looking flowering spike unlike kochia's small clusters of flowers, and has a characteristic five-spined fruit.

Chenopodiaceae. Leaves: linear to lanceolate; largest leaves, found toward base of plant, are 1.6-2.4 in (40-60 mm) long, 0.04-0.14 in (1-3.5 mm) wide, flat, untoothed, and alternate. Bassia flowers between July and October. Inflorescence: spike 0.2-2 in (5-50 mm) long, with oblong, leaf-like bracts 0.08-0.2 in (2-5 mm) long that often wither in fruit. Flowers: tiny, without petals, in axillary groups of one to a few; 5 stamens and 2 or 3 stigmas. Calyx is tan, densely woolly, becoming leathery; attached to the calyx are 5 incurved, hooked spines about 0.04 in (1 mm) long. Fruit: including the persistent calyx, is 0.04-0.06 in (1-1.5 mm) in diameter, containing a single dark brown seed about 0.04 in (1 mm) long (Munz and Keck 1973, Hickman 1993).


Hickman (1993) reports that bassia occurs widely in California, except in the Klamath and northern Coast Ranges and in the Sierra Nevada above 1,200 meters (about 3,900 ft). It appears to do well on basic or saline soils. Robbins et al. (1970) report the occurrence of bassia in the "spiny salt bush association" of the San Joaquin Valley. It is also common in abandoned agricultural fields in the Owens Valley, the Mojave Desert (Lancaster), the Colorado (Imperial Valley) Desert, the South Coast (Santa Ana River), and northward through the Sacramento Valley (Robbins et al. 1970, Sanders, pers. comm.). It is also known from the Sierran foothills, such as near Mount Lassen in the north and Lake Isabella (Kern River) in the south (Ahart, pers. comm., Hewett, pers. comm.). It may also occur in extreme northern California, near Tulelake, on the Modoc Plateau.


Bassia is native to parts of Europe and Asia, particularly around the Caspian Sea. It was first recorded in North America near Fallon, Nevada, about 1915 (Collins and Blackwell 1979). It probably was introduced as a seed contaminant, possibly with Turkestan alfalfa (Medicago sativa) seed (Alex 1982). It was found as early as 1921 near Los Banos in the San Joaquin Valley. By 1940 it could be found in spiny saltbush (Atriplex confertifolia) and mixed lowland associations of the San Joaquin, Owens River, Santa Ana River, Imperial, Coachella, and Palo Verde valleys (Robbins 1940). It had also spread to neighboring Arizona and as far as British Columbia and Wyoming, growing well in soils too alkaline for crops. By this time bassia was also established on the East Coast, where it has maintained a limited distribution from Maine to New York City.

Considering the external structure of the fruit, bassia seeds probably disperse by attaching to the fur or feathers of passing animals (Collins and Blackwell 1979). Human disturbances, such as road building or ditch clearing, help to establish bassia and likely contribute to dissemination as well. The seeds do not survive well in fresh water for extended periods (Bruns 1965).


Bassia occasionally may displace native species, but there is no evidence that it alters other ecosystem processes (e.g., fire cycles, hydrological cycles, soil chemistry, etc.). On The Nature Conservancy's Kern River Preserve, in the southern Sierra, bassia covers five to ten acres (2 to 4 ha) in a multitude of small clusters, becoming a monospecific stand in the densest areas. Once established, it is somewhat persistent, although it does not appear to be on the increase at the Kern River Preserve. In some areas native species are replacing bassia (Hewett, pers. comm.), suggesting that it is possibly ruderal or stress-tolerant rather than competitive. Because it is toxic to sheep, bassia can be a threat to livestock (James et al. 1976).


Bassia is an annual, reproducing by seeds (Muenscher 1955). Its germination and growth patterns have not been extensively studied (Collins and Blackwell 1979).


However, the following can be inferred from the plant's environmental preferences and from the habits of its close relatives: seed dormancy is relatively short; germination requires warm, high-light conditions; germination and seedling growth are not hindered by moderately saline/alkaline conditions; and initial growth is rapid, especially below ground.

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Physical control:  

Mechanical removal: Muenscher (1955) recommends hand pulling of bassia, done most easily after a rain when soil is loose. Plants should be pulled as soon as they are large enough to grasp but before they produce seed. Pieces of root remaining in the soil will not sprout again. Plants can be destroyed readily while they are still small by hand hoeing, either by cutting off the tops or by stirring the surface soil to expose seedlings to drying by the sun.

Prescribed burning: This might be a useful control strategy for bassia, though it has not been tried. Because bassia produces flowers and seeds later in the season than do most rangeland plants, there may be a period in mid-summer during which desirable plants have senesced and dropped seed but bassia has not. If such a window exists, dry senesced plants could provide enough fuel to kill bassia before it produces seed. However, most reported infestations of bassia are sparse and limited in extent, so that presence of this weed alone may not justify burning.

Biological control:  

Insects and fungi: The only mention of insect herbivory in the literature is of Lygus sp. leafhoppers feeding on bassia in late summer (Parker 1972). The degree to which these insects affect the growth of bassia was not reported. No program currently exists for biological control of bassia.

Grazing: Livestock readily graze on bassia, although sheep have died after a single feeding (James et al. 1976). Goats have not yet been used to control bassia.

Plant competition: Experience at the Kern River Preserve suggests that minimizing disturbance in non-crop settings may allow more desirable plants to outcompete and replace this weed.

Chemical control:  

Chemical control of bassia has not been reported, although it might be similar to control of other similar species, such as kochia and Russian thistle. Kochia and Russian thistle are well controlled by metsulfuron, triasulfuron, thifensulfuron + tribenuron, or tribenuron at label-recommended concentrations. Herbicide-resistant populations of kochia are known to arise, and this can be minimized by tank-mixing these sulfonylurea herbicides with other broadleaf herbicides with differing modes of action.

Russian thistle can also be controlled with dicamba, 2,4-D, and picloram plus 2,4-D at 1-1.5 fl oz/acre + 0.75 pt/acre. Kochia can also be controlled with dicamba plus MCPA amine at label strengths. 2,4-D at 1.0 pt/acre gives good kochia control, but good spray coverage is essential because 2,4-D does not translocate readily in kochia. Treatment should be to small plants (less than three inches tall), or large spray volumes should be used to penetrate the kochia foliage. The esters of 2,4-D generally are more effective than the amines for both weeds. MCPA is not as effective as 2,4-D in controlling either weed. However, MCPA at 1.0 pt/acre will control small kochia plants. Picloram is not effective on kochia; but control is good when it is combined with 2,4-D ester at 0.75 pt/acre (North Dakota State University Extension Service 1998). Because bassia infestations occur in non-agricultural areas and tend to be limited in scope, spot spraying (not broadcast) is the preferred method of herbicide application in most cases. Check herbicide labels for current registered uses in California.