Bromus is a large genus of the true grass family (Poaceae), with about 160 species. Estimates in the scientific literature of the number of species have ranged from 100 to 400. They are commonly known as bromes, brome grasses or chess grasses
Bromus species are generally considered to have low utility value to humans. As names like Bromus fibrosus, Poverty Brome (B. sterilis) or Ripgut Brome attest, they are not very useful as fodder because their leaves sclerotize quickly and may even be harmful to livestock due to the high silica content. Brome grasses are not usually found as ornamental plants due to most species' nondescript appearance. Some are useful to prevent erosion but such use must be cautiously controlled as most Bromus have the ability to spread, becoming invasive weeds.
Cirsium arvense is a species of Cirsium, native throughout Europe and northern Asia, and widely introduced elsewhere. The standard English name in its native area is Creeping Thistle.
The species is widely considered a weed even where it is native, for example being designated an "injurious weed" in the United Kingdom under the Weeds Act 1959. It is also a serious invasive species in many additional regions where it has been introduced, usually accidentally as a contaminant in cereal crop seeds. It is cited as a noxious weed in several countries; for example Australia, Brazil, Canada, New Zealand, and the United States. Many countries regulate this plant, or its parts (i.e., seed) as a contaminant of other imported products such as grains for consumption or seeds for propagation. In Canada, Cirsium arvense is classified as a primary noxious weed seed in the Weed Seeds Order 2005 which applies to Canada's Seeds Regulations.
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Bromus - Wikipedia
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