Burrweed. We spend a lot of time barefoot here at the farm… or we USED to before this little bugger showed up and has run amok all over the farm. But I am declaring war this year.
A winter annual, burrweed sprouts in December or so and sets an extremely spiney and painful seed in early spring. These stabby seeds stick in the bottom of shoes and stick to the bottom of dog’s paws. It is common in high traffic areas where grass is kept low.
If you are going to treat your barnyard, pasture, etc for burrweed – you need to do it after the plant emerges and before it sets seed.
UGA extension put out an article about controlling burrweed (You can read the full article here). The article talks about how to control the pesky spiney weed:
The best way to control burweed is to treat your lawn for the weed in December, January or February. This allows you to kill the burweed before it has a chance to form the spiny seeds. A preemergent herbicide like Atrazine or Pendamethalin applied to your lawn in January or February is a very effective way to control burweed and lots of other winter weeds. If you notice that some of the burweed has slipped by the first application, you could use an alternate herbicide such as 24-D, Trimec, or Mansion in early March to kill the remaining plants before they develop seeds.UGA Extension office
If you see one or two plants, you can “remove them manually” (aka dig them up – I particularly enjoy kicking the buggers with the toe of my boot.)