For a couple of years I've been dealing with a thorny issue in late summer/early fall. I've got some sort of grassy plant that comes up around the same time as regular crabgrass, only when it produces a seed head, instead of the regular crabgrass type of seeds, it produces little spikeballs. They look kind of like the ancient mace weapon - a round ball around 1/8" in diameter with little straight spiky thorns on it. The thorns are incredibly sharp, they'll go straight through a regular leather work glove, and just brushing it against them with bare skin will end up with them stuck in your finger/foot/whatever.

Do you have any idea what they are and how to control them? So far I've just been trying to be very vigilant about pulling them out whenever I see them and disposing of them so they don't reseed. A couple of my neighbors' yards have them as well. I've tried putting down Scotts with Halts but that doesn't seem to really help.