Yellow Star Thistle
With experience, you can recognize these plants when they first emerge. The gray-green color is distinctive, and the leaves are a little hairy. If you can, you want to pull these plants before they flower and form their long nasty thorns. Pulling yellow star thistle is a fairly simple hands-on experience. It is important to wear gloves because there is an unfriendly component in the plant juices that you do not want to absorb through your skin. Without gloves, even after pulling just a few plants, you can get an odd taste in the back of your mouth from the contact of the plant with you skin. With repeated lengthy contact, you can start to feel stiff and achy in your back, and get sore kidneys. But as long as you wear gloves, wash your hands before eating, and wash the clothes you wear while pulling the star thistle, you will be fine, even doing lots of pulling.
Like all weeds, star thistle is a lot easier to pull when the ground is damp and willing to give up the roots. Because it is an annual, as long as you get some root with the stem, you have got enough to stop it from growing more.
Because of the thorns, star thistle is a little hard to pack into plastic garbage bags without ripping the bags. However, if you can get them into black plastic garbage bags with minimum ripping, add a cup of water to the bag, tie it shut, and bake it in the hot sun until the plants are slimed, rotten and nasty, and the seeds will no longer be viable. Then they are safe to compost.
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