Bull thistle (Cirsium vulgare), also sometimes called spear thistle, Fuller's thistle, and lance-leafed thistle, is a ...

There are more than 62 varieties of native thistles (Cirsium) in the United States. Native thistles are not considered noxious weeks. They occur naturally in regions where they evolved and are a ...

Cobwebby thistle (Cirsium occidentale), for example, also known as western red thistle or snowy thistle, is native to the southwest region and is a particularly good option for attracting the ...