Toxic Parts:
soluble oxalates
Flower Color:
  • flower color
meadows, coastal, xerophyte

Time of Greatest Risk


Geographical Distribution

Fivehook bassia distribution - United States

Related Species

Fivehook Bassia

Bassia hyssopifolia

Fivehook Bassia, Smother Weed
5/ 10
Fivehook bassia (Bassia hyssopifolia) is an erect summer annual that is found growing as a common weed across most of the western United States. It is native to Europe and Asia, but has been introduced to North America, South America and Australia. Fivehook bassia is a facultative wetland indicator species, and is often associated with alkaline areas.

Fivehook bassia has the following attributes:
  • Height: Grows to 4 ft in height or more.
  • Leaves: Produces alternate, flat, linear-lanceolate to lanceolate, gray-green leaves that are covered with soft hairs.
  • Flowers: It produces clusters of inconspicuous flowers that lack petals. They form off the bases of leaf stalks and stem ends. Flowers bloom late summer to early fall.
  • Fruit: Have five small 1-mm long hooked spines.
  • Root system: Taproot, usually with few to several branched, fibrous lateral roots.

Fivehook bassia appears similar to lambsquarters (Chenopodium album), and is distinguished by its smaller, elongated and pointed leaves.

Toxic components
B. hyssopifolia is able to accumulate high levels of oxalates, which can lead to nutritional secondary hyperparathyroidism in horses. Levels of oxalates vary depending on environmental conditions, stage of growth of the plant, season, and plant part consumed. B. hyssopifolia has been the cause of many cases of oxalate poisonings in livestock over the years. B. hyssopifolia also has the potential to accumulate high levels of nitrates, leading to increased risk of nitrate poisoning.


  • Colic
  • Lameness
  • Swelling Of Head
  • Diarrhea
  • Weakness
  • Incoordination
  • Coma


MANUAL CONTROL: Small numbers can be pulled by hand, easiest following a rain after the soil loosens. When digging, sever the root below the soil surface. Mowing can reduce seed production, however you must mow before the flowering stage to prevent seed production.

CHEMICAL CONTROL: Recommended herbicides include dicamba, fluroxypyr, glyphosate, chlorosulfuron, imazapic, imazapyr, and metsulfuron.