Whenever nervous gardeners start quaking in fear on the subject of poisonous plants anywhere near their darling children, I usually give a stock answer... " There are very few plants lurking outside of your door plotting attacks on unwary suburbanites."
You notice I said very few. This is one of the very few.
Allow me to introduce the current bane of my existence.
This is burr grass.
Aka sticker weed and also known as 'that (insert 1 to 5 of your favorite cursewords here) weed'
Its vile. It has no practical use or purpose for existence. Satan made them. I'm serious.
Anyone who walks outside, especially from midsummer on, comes in covered with them from the knees down. Every time a dog has to use the yard, he will return limping with burrs between his toes. Which makes it very difficult to convince the dogs go outside.
Burrs get everywhere.
If you don't thoroughly clean them of your socks, they'll get in you laundry And knit themselves into the towels, t shirts and, the absolute worst, your underwear. Not only are you unable to walk outside barefoot, but the carpet in your house can become an experience similar to walking on pins and needles.
Control of them Is difficult.
Hand weeding works, provided your lawn isn't an acre, like this one is.
Regular watering of the lawn promotes the growth of the grass, and that will crowd out the burrs. But between the current drought and the accompanying water restrictions, and again, an acre of land... not really practical.
I see on the web that periodically burning the lawn,
about every 7 years, keeps it under control. Drought, burn bans, water restrictions. Not gonna happen.
Spray the individual weeds with either roundup or vinegar, preferably before they produce burrs. The problem is that before they produce burrs, they look just like the rest of the grass.
It's all very annoying.