• Source: Ambrosia psilostachya

Ambrosia psilostachya is a species of ragweed known by the common names Cuman ragweed and perennial ragweed, and western ragweed.




Distribution and habitat


The plant is widespread across much of North America (United States, Canada, and northern Mexico). It is also naturalized in parts of Europe, Asia, Australia, and South America. It is a common plant in many habitat types, including disturbed areas such as roadsides.




Description


Ambrosia psilostachya is an erect perennial herb growing a slender, branching, straw-colored stem to a maximum height near two meters, but more often remaining under one meter tall. Leaves are up to 12 centimeters long and vary in shape from lance-shaped to nearly oval, and they are divided into many narrow, pointed lobes. The stem and leaves are hairy.
The top of the stem is occupied by an inflorescence which is usually a spike. The species is monoecious, and the inflorescence is composed of staminate (male) flower heads with the pistillate heads located below and in the axils of leaves. This bloom period is from June through November.
The pistillate heads yield fruits which are achenes located within oval-shaped greenish-brown burs about half a centimeter long. The burs are hairy and sometimes spiny. The plant reproduces by seed and by sprouting up from a creeping rhizome-like root system.




Ecology


Ambrosia psilostachya is a host plant for the caterpillars of Bucculatrix transversata, Cosmopterix opulenta, Exaeretia gracilis, Gnorimoschema saphirinella, Schinia sexplagiata; the beetles Calligrapha disrupta, Calligrapha suturalis; and the grasshopper Spharagemon collare.




Medicinal uses


This plant had a number of medicinal uses among several different Native American tribes, including the Cheyenne, Kumeyaay (Diegueno), and Kiowa people.




Chemistry


Ambrosia psilostachya contains a group of phytochemicals called psilostachyins.




References






External links


Calflora Database: Ambrosia psilostachya (Western ragweed)
Jepson Manual eFlora (TJM2) treatment: Ambrosia psilostachya
USDA National Forest Service, FEIS Ecology of Ambrosia psilostachya
USGS.gov: Northern Prairie Wildlife Profile
UC Calphotos Photos gallery of Ambrosia psilostachya

Kata Kunci Pencarian:

• Ambrosia psilostachya
• Ragweed
• Eastern cottontail
• Bucculatrix transversata
• List of Canadian plants by family A
• Gnorimoschema saphirinella
• Psilostachyin
• Schinia sexplagiata
• Exaeretia gracilis
• List of invasive plant species in the Northern Territory