''Ambrosia tomentosa'', the skeletonleaf bur ragweed, silverleaf povertyweed, or skeleton-leaf bursage, is a

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

n species of

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

plants in the family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...

. Skeletonleaf bur ragweed is native to the west-central part of the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, primarily the western

Great Plains The Great Plains (french: Grandes Plaines), sometimes simply "the Plains", is a broad expanse of flatland in North America. It is located west of the Mississippi River and east of the Rocky Mountains, much of it covered in prairie, steppe, an ...

, the

Colorado Plateau The Colorado Plateau, also known as the Colorado Plateau Province, is a physiographic and desert region of the Intermontane Plateaus, roughly centered on the Four Corners region of the southwestern United States. This province covers an area of ...

, and eastern

Great Basin The Great Basin is the largest area of contiguous endorheic basin, endorheic watersheds, those with no outlets, in North America. It spans nearly all of Nevada, much of Utah, and portions of California, Idaho, Oregon, Wyoming, and Baja California ...

. It is often found growing alongside roads and in the sandy parts of plains. It is considered a

noxious weed A noxious weed, harmful weed or injurious weed is a weed that has been designated by an agricultural or other governing authority as a plant that is injurious to agricultural or horticultural crops, natural habitats or ecosystems, or humans or liv ...

in several states. It is also considered a severe

allergen An allergen is a type of antigen that produces an abnormally vigorous immune response in which the immune system fights off a perceived threat that would otherwise be harmless to the body. Such reactions are called allergies. In technical terms ...

Description

''Ambrosia tomentos'' grows up to 3 feet (91 cm) tall. The deeply lobed hairy leaves grow to 5 inches (12.7 cm) and have toothed margins. Flowers are small and yellow and produce spined 2-seeded burrs. In addition to seeds it can also reproduce via its widely spreading roots.Idaho's Noxious Weeds – Skeletonleaf Bursage
Retrieved 2010-03-25.Flora of North America Vol. 21 Page 17 ''Ambrosia tomentosa'' Nuttall, Gen. N. Amer. Pl. 2: 186. 1818.
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References

External links

tomentosa Flora of the Western United States Flora of the North-Central United States Flora of the United States Flora of the South-Central United States Flora of the Great Basin Flora of the Great Plains (North America) Plants described in 1818 Taxa named by Thomas Nuttall {{Heliantheae-stub