''Xanthium spinosum'' (also known as ''Acanthoxanthium spinosum'') is a species of flowering plant in the aster family known by many common names, including spiny cocklebur, prickly burweed and Bathurst burr. This species is part of the genus ''Xanthium'' that encompasses 25 different species of flowering plants of the daisy family, Asteraceae, and sunflower tribe.

Distribution

It is known worldwide as a noxious weed that grows in many types of disturbed habitats such as pastures, crops, waterways, grasslands, flood plains, waste areas, and sometimes tropical and arid environments. Its original native range is not known but it may have come from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

,Flora of North America
/ref> possibly from

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

.Washington State Noxious Weed Control Board
The plant is found in various regions across the world including Canada, the US, Central America, parts of Africa and the Middle East, China, Russia and Australia.

Description

''Xanthium spinosum'' is an upright, highly branched, dichotomous, annual herb producing a slender stem up to tall or slightly taller. It is lined at intervals with very long, sharp, yellowish, three pronged spines which may exceed three centimeters in length. These spines are typically found at the base of each leaf fork. The leaves are irregularly lobed or lance-shaped lobed, the middle is much longer than the others, and have white veins down the center. They are arranged spirally or alternately along the stem. Each is up to 10 or 12 centimeters long and are dark green or grayish on top, pale green or whitish underneath and are covered in downy hairs. ''Xanthium spinosum'' flowers between summer and late fall, typically from July to October in the northern hemisphere. The plant produces male and female flower heads that are monoecious and form greenish axillary or solitary inflorescence clusters. The male flowers are bulbous and found in dense clusters at the tips of stems near the topmost leaves. Female flowers are found at the leaf forks on lower leaves and develop into burs. The

bur A bur (also spelled burr) is a seed or dry fruit or infructescence that has hooks or teeth. The main function of the bur is to spread the seeds of the bur plant, often through epizoochory. The hooks of the bur are used to catch on to for exam ...

s are one or 1.5 centimeters long and covered in small hook-like spines. Each bur has two seeds inside it that are flattened and have a thick coat. The spiny burs are easily dispersed to new areas when they become attached to animals, people, and objects, or float on water. Xanthium spinosum sl18

Uses

''Xanthium spinosum'', as well as others within the genus, are used in many traditional medicinal treatments. The chloroform extracts found in the plant are used to treat numerous ailments such as hydrophobia, rabies, fevers, diarrhea, and cancer. In Chinese medicinal practices, the methanol extracts found in the leaves and fruits are used to treat inflammatory diseases such as rheumatoid arthritis. This species can also be toxic to humans, as it produces toxins that cause nephrotoxic effects, causing damage to the kidneys.

Agricultural & ecological effects

''Xanthium spinosum'' is classified as an invasive weed of many crops. This plant negatively impacts crops such as: cotton, maize, sunflowers, tomatoes, soybeans, sugarcane, and other annual or perennial crops. It decreases the health of the ecosystem it takes over and threatens the loss of the native species that inhabit the area as well as lowers the biodiversity. It also threatens the health and well being of the animals that inhabit the areas where it is found. If livestock ingests ''Xanthium spinosum'', the livestock will become poisoned and could potentially make its way into a human. The plants, especially new seedlings, are

toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subs ...

livestock Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animal ...

. This plant is also toxic to humans. Bur damage to

sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to domesticated ...

wool Wool is the textile fibre obtained from sheep and other mammals, especially goats, rabbits, and camelids. The term may also refer to inorganic materials, such as mineral wool and glass wool, that have properties similar to animal wool. ...

reduces its value.

References

External links

*
Jepson Manual Treatment of ''Xanthium spinosum''
— ''invasive plant species''.

— ''invasive plant species''.
University of California, Calphotos Photo gallery
— ''invasive plant species''. {{Taxonbar, from=Q643890 spinosum Flora of South America Plants described in 1753 Taxa named by Carl Linnaeus