Also known as Barnaby’s thistle, golden starthistle, or yellow knapweed, it sends deep roots into the soil, depleting the moisture so no other plant species can establish. It outcompetes native ...

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 Keri Wilson, horticulturist and writer for Garden Media Group, points out, ...

There are 20 thistles native to Colorado, besides being prickly, they are desirable plants. Thistles are in the Asteraceae, sunflower (daisy) family.

Our Mystery Plant is a thistle, and I was able to enter a patch of this stuff on a recent field trip in the upstate of South Carolina. Spiny stuff!

Canada thistle (Cirsium arvense) is an aggressive, invasive plant. Here's how it spreads and how to identify it so it doesn't take over your garden.

Canada thistle (Cirsium arvense) was one such plant when we moved to Northeast Ohio five years ago.The blue-gray foliage of the rosette-shaped seedlings looked intriguing during spring, and in the ...

Check thistle plants weekly and reapply as needed. Q: ... houseplants, fruit, vegetables and herbs, insect and disease issues and identification of unknown plants or insects.