[pct-l] Caltrops?

[mardav@charter.net (Marion Davison)]

Fascinating.  I ride a mountain bike many miles a week here in the high desert
(Victorville) and I have solid inner tubes.  Here in the high desert we have a
native plant that produces a thorn called a goathead.  Like the caltrops device
pictured, the thorn is naturally designed to always fall with one vicious point
sticking straight up.  They are murder on dog paws, bare feet, and bike tubes.
It is about the size of a bb and rock hard.  They are scattered everywhere in
the high desert.  Sort of nature's land mine for bikes.  I spent my childhood
barefoot in Orange county, but between the desert ants and the goatheads, one
can never be barefoot here.
Marion Davison, "llamalady"