The purple flower heads may look pretty, but don't let that fool you. Milk thistle (Silybum marianum) can be a pain if it's growing in your yard. It's non-native and can be an invasive plant ...

From May through October, you'll find five-petalled, papery white to pale purple notched flowers floating above the grass. They spread via seeds and stray plant parts. Since musk thistle (Carduus ...

The Sacramento Mountains thistle is a rare purple flower than can grow to be six feet tall and lives only in wet, high-elevation habitats in the Sacramento Mountains near the town of Cloudcroft, New ...

The Yakima County Noxious Weed Board has been helping landowners control problem and noxious weeds since 1975. Contact them at 509-574-2180, email [email protected] or visit ...

European marsh thistle, a terrestrial and wetland herbaceous biennial in the Asteraceae family, is an invasive plant that prefers moist soils ... and spiny teeth along leaf margins flowers are purple, ...