Here in Thailand we've found a unique way to stop grasshoppers ("dtaggatan") from eating our crops.  We eat them.  They're collected in the feilds are fried ("dtaggatan tort"), a great snack that is known to be extremely nutritious.  The Kloeng Toei Market in Bangkok has a fresh selection of grasshoppers that are specially farmed for sale to hundreds of insect sellers who make a living selling all sorts of fried insects from "jing reet" (crickets) to "rot duan" (bamboo worms).  When travelling in Bangkok keep an eye out for these vendors and don't be scared to try these delights...snacks that go really well with a nice cold beer.