Controlling Bindi-is

Um what is or are 'Bindi-is'?

Ditto?

Soliva pterosperma.

You know, those really annoying things that spike your feet every time you walk on the lawn in summer. (But maybe they're only an Australian weed?)

Ah right not something we have in the UK and from googling not in most of the States either. It is a South American native and doesn't sound to be a fun plant. Only advice I've seen is to get hold of as low as possible and pull out, seems spraying is not a good idea the burrs still remain for you to walk on.