Slenderflower Thistle & Turkish Thistle

Slenderflower Thistle - Grows up to 6.5 feet tall with loose hairs on the stem.

Leaves: Leaves are 4-10 in. around the base of the plant with 6-10 spines. Leaves sometimes have light wooly hairs and get smaller as you move up the stem.

Flowers: Flowers bloom from June-July. Clusters of 5-20+ pink flowers are usually found near the tops of the stems.

Habitat: Dry open areas like pastures, ranges, right-of-ways, and areas of soil disturbance.

Weed Classification: A

Why is it a Noxious Weed?

Slenderflower thistle invades and spreads quickly on ranges and pastures and will outcompete native and desirable vegetation.

Turkish Thistle - Annual thistle with winged stems that grows up to 4 feet tall.

Leaves: Basal leaves are about 4 inches long and reduce in size moving up the stem. The leaf bottoms are woolier than the tops.

Flowers: Flowers bloom May-July. Flowers appear almost compressed, being more slender towards the top. They are pink in color and often on short stems below the flower.

Habitat: Canyon grasslands and rocky slopes are where it is found most often.

Weed Classification: A

Why is it a Noxious Weed?

Readily spreads and infests areas, outcompeting native and desired vegetation.

These thistles can be hard to identify and may be confused with other thistle species. If you think you have one of these thistles, please let us know and we can help with identification.

Control Recommendations:

WA State Noxious Weed Control Board - Slenderflower

WA State Noxious Weed Control Board - Turkish

PNW Pest Management Handbook