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, as ...

Bull thistle starts out life as a prickly ground-hugging rosette that, in the summer, puts out tall, equally spiny stalks topped with purple flowers. Later, fluffy white seed heads form.

It is known as musk thistle in some countries overseas. The species gets the name "nodding thistle" because of the large seed heads that "nod" over due to their weight, for example, they tend not to ...

Soil Conservation Technician When I moved into this new house, I was thrilled to see a large planted flower bed in the backyard. All spring I imagined what beautiful flowers would soar up and ...

Winged thistle is a winter annual, which means it generally establishes from seed in autumn, grows as a typical thistle rosette over winter, then develops an upright flower stem in spring, from which ...

Like many other biennial invasives, bull thistle is able to produce a large seed bank that can remain viable for up to 10 years! As a result, the plant can easily spread and form dense stands in ...