We've got goat heads and russian olive (major thorns). Since there is a limit to how many tubes I can carry, and how many disposable dollars are hanging around, I patch. So far, I've always been able to replace a tube, and save the patching for home. Keeping fingers crossed.
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Some people are like a Slinky ... not really good for anything, but you still can't help but smile when you shove them down the stairs.