Ohio State University Extension Bulletin 866-98

Identifying Noxious Weeds of Ohio

Bulletin 866-98


Musk Thistle
(Carduus nutans)

Habitat: pastures, meadows and wasteland including roadsides

Life cycle: biennial

First Year Growth Habit: A basal rosette. Leaves are waxy and pale green with few hairs.

Second Year Growth Habit: large, coarse, branched plant that can grow up to 9 feet

Leaves: 3-6 inches long, alternate, spiny, deeply lobed, long and narrow

Stem: stems covered with dense, short hairs and spines

Inflorescence: June - October. Purple thistle-like flowers, 1-2 inches in diameter, with spiny-tipped bracts surrounding inflorescence. Often the flower heads droop or nod.

Fruit: white or tan pappus

Similar plants: In the first year of growth, musk thistle may resemble bull thistle (Cirsium vulgare). However, the leaves of bull thistle are covered with hairs. Musk thistle is also referred to as nodding thistle.

The problem is.... This prickly weed reduces the quality of grazing land. It has spread quickly throughout much of the Midwest, but is not yet common in Ohio. Avoid handling without gloves.

inflorescence of musk thistle

The inflorescence of musk thistle is 1-2 inches in diameter.

spines that cover nearly every part of this plant

The spines that cover nearly every part of this plant make it truly worthy of the Identifying Noxious Weeds of Ohio "noxious."

musk thistle


Back | Forward | Table of Contents