Bull thistle (Cirsium vulgare), also sometimes called spear thistle, Fuller's thistle, and lance-leafed thistle, is a biennial weed found in almost every state and territory in the USA ...

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 ...

European marsh thistle, a terrestrial and wetland herbaceous biennial in the Asteraceae family, is an invasive plant that prefers moist soils. European marsh thistle frequently invades fens, wetlands, ...

Scotch thistle is the most common thistle species in New Zealand with spines on both the leaf surface and margins. Scotch thistle is a biennial weed, so it depends quite heavily on the establishment ...

Bull thistle, a member of the Asteraceae family, is yet another herbaceous biennial on our list of invasives. Unfortunately, bull thistle can flourish in an array of sites ranging from meadows, ...