Anyone who has property (especially for livestock) around here knows how quickly thistle can take over in fields. Though it has it’s medicinal properties, it is an aggressively invasive plant with poison-laced stickers and barbs that can cause festering wounds. 

Many feel the need to spray their fields with poison to curb the plants’ spread. They are content to reseed and consider it as good as new. Luckily, Papa is not of this mindset or I would find myself cringing as the procedure took place, thinking of the poison that would then tant the soil for years to come. 

Papa taught me to chop thistle instead. The key to thistle is knowing its lifecycle. A seed springs a plant that grows and then lies dormant the first year. The next year it grows more, flowers, seeds, and dies. Because of this lifecycle, you can wait until the plant flowers, chop it down and it will not come back. It must be timed right so to keep the flowers from going to seed. We clip, bag, and burn the flowers. Then, we clip the plant as close to the ground as possible and leave it in the field. 
It takes more effort and time to use this natural method, but you don’t have to worry about toxins in your soil. It will take over two years to notice a difference so understand that you are in it for the long haul. Don’t get discouraged. It’ll be easier to upkeep after the first few years.