Invasive Thistle Spreads With The Wind

By Phran Novelli

PHILADELPHIA (CBS) - The other day we were out for a ride when it seemed like a swarm of insects was crossing the road - you could see a big cloud of some stuff in the air up ahead. Getting closer, it was easy to see they were actually millions of thistle seeds caught in the breeze.

If you've ever had thistles turn up as weeds in your garden, you know how nasty they can be. What's commonly called Canada thistle is actually not from North America at all but an alien plant, from Europe and the Mediterranean, and they've plagued farm crops for centuries too.

Prickly to touch and hard to get rid of - if you pull a thistle and leave any part in the soil, it will regenerate into more thistles. And since they spread so easily on the wind, if you let their purple flowers bloom and go to seed, they'll soon be in everyone else's yard too.

So if you spot some thistles at your place, at the very least, cut off the tops and put them in the trash before their flowers can turn to fuzzy puff balls and take a ride on the next gust of wind and into everyone else's garden.