Sandburrs. I really hate these things. They get in the dogs' feet and I don't like that. When Em is out on the prairie and gets one she will just stand, raise her foot, and look around for me to come to the rescue. I always carry the proper tools (Kelly forceps are good) in the Rhino so I can perform the operation when called for.
Yesterday in the back pen attached to the shop building, Jack limped over to me and raised his left front paw. At first I couldn't find anything, but then found a burr deep down in his pad. It was "old and tired" and easy to remove and Jack was off again on his endless search for adventure. Didn't even say thanks.
Those little green "starbursts" get hard as they age and the spikes are amazingly sharp. Barbed, too, so they stick to whatever picks them up. They also seem to have something on them that causes the stuck place to sting and burn for a long time after they are extracted.
I've just about eradicated these things inside the compound. Shortly after being spotted this one, growing up through the auto-gate, got a nice dose of Round-Up.