Answer: If the thistles are small they are quite easy to pull if the soil is moist. Alternatively, you can hoe them off at ground level several times and exhaust their root systems that way. You can also smother them under a layer of newspaper or cardboard topped off by mulch. You could also use an herbicide containing glyphosate, being careful to read and follow all of the label instructions. In the future, try not to allow any nearby thistles to go to seed.
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