Musk Thistle
Scientific Name:
Carduus nutans
Type:
Herbaceous Plant
Habitat:
Sagebrush, open woods, pastures, rangelands, roadsides and abandoned lands
Range:
Native to western and central Europe; widespread across much of North America
Status:
No listed status
This species is
INVASIVE
to the Truckee Meadows.
Identification:
Musk thistle forms a rosette of 6 to 8 leaves in its first year, the leaves are up to 1 foot long and 6 inches wide. The leaves are covered with wooly hairs. In its second year musk thistle sends up a flower stalk that can be up to 8 foot tall! Stem leaves are 3 to 6 inches long and spiny. Stems have spiny wings their full lengths except for a few inches below flowerheads. The pink flowerheads are large, 1.5 to 3 inches in diameter, with numerous large, lance-shaped, spine-tipped bracts that look like a pinecone.
Fast Facts:
Musk thistle was first noticed in central Pennsylvania in 1852. It probably came to the US in ballast water in ships from Europe.
A single plant can produce 11,000 seeds! These seeds are eaten and dispersed by birds and small animals.
Musk thistle appears to release chemicals into the soil which inhibits the growth of other plants around it. This type of chemical warfare is called allelopathy.
Livestock and wildlife avoid eating the spiny musk thistle. It is very competitive and can form stands of up top 60,000 plants per acre!
Musk thistle is native to western and central Europe, it was introduced into North America in the 1800s. As of 1999, musk thistle was reported to occur in 45 states in the U.S. and all of the southern Canadian provinces.
Musk thistle is an invasive weed in the Truckee Meadows. It is classified as a Category B noxious weed by the Nevada Department of Agriculture.
Musk thistles have been observed in disturbed areas throughout the Truckee Meadows, including Oxbow Nature Study Area.
Sources:
https://www.fs.fed.us/database/feis/plants/forb/carnut/all.html
Invasive Plants, A Guide to Identification and the Impacts and Control of Common North American Species. Sylvan Ramsey Kaufman & Wallace Kaufman. 1st Edition 2007
https://www.fs.fed.us/database/feis/plants/forb/carnut/all.html
https://agri.nv.gov/Plant/Noxious_Weeds/WeedList/Musk_thistle_(carduus_nutans)/
Image: F. D. Richards, https://www.flickr.com/photos/50697352@N00/7558378982/, license https://creativecommons.org/licenses/by-sa/2.0/, cropped from original.
Image: Sarah Ward, https://www.flickr.com/photos/127338544@N06/41154350180/, license https://creativecommons.org/licenses/by/2.0/, cropped from original.
Image: Matt Lavin, https://www.flickr.com/photos/plant_diversity/5841904841/, license https://creativecommons.org/licenses/by-sa/2.0/, cropped from original.
Contributor(s):
Emma Wynn (research & content)
Alex Shahbazi (edits & page design)