Canada Thistle

Canada Thistle (Cirsium arvense)

You will spot this plant throughout the field- and watch out if you're walking off-path through the vegetation! This is a very prickly invasive herbaceous plant. Is commonly found in disturbed environments such as this old field and establishes in many soil types, found in most plant communities in this area. It likes high light and drier soils, though it is very resilient and will establish in many locations.

Key identifying factors:

- Green, slender, freely branched with oblong alternate leaves with deeply pinnately segmented, spiny margins.

- Frilly purple flower heads occurring in mid to late summer.

- In some areas this plant may be poking up above the grass layer, and easier to spot.

Many wildlife species enjoy using this plant. Pollinators come to its flowers for nectar with over 80 insect species visiting it. Over 130 wildlife species forage on the vegetation such as white-tailed deer which are present. Livestock does not prefer this plant and will avoid even plants that they enjoy if thistle is present.

Though this is a very tough weed, it is a good plant to know and produces such delicate flowers that juxtapose the spiny leaves beautifully. It is a striking plant.