Spinosad, works well on chewing insects like grasshoppers. It's organic, look for it as an ingredient in several brands of pesticide. Bonide has it in their "Captain Jack's Dead Bug Brew". It's fairly benign for beneficial insects, including bees, but work really well against chewing insects.

Spinosad is not that effective on grasshoppers. Chickens, however, are a good organic solutions, plus you get some good poop to compost.

"Once grasshoppers have invaded the garden, insecticides won't be very effective and must be reapplied every few days as long as the invasion continues; read the product label to determine the allowable frequency of applications. Carbaryl and other insecticides such as cyfluthrin or other pyrethroids commonly used as sprays for grasshopper control are very toxic to bees, natural enemies of grasshoppers, and aquatic life, although carbaryl in bait form is less hazardous to bees. Reserve the use of insecticides for serious situations where they may provide a significant level of control, ideally as baits around the edge of the garden before grasshoppers invade."

From UC Davis Grasshopper management

More info. on spinosad - grasshoppers are not on the list of pests is controls. The directions tell when to spray as to avoid bees. After it has dried 3 hours, it is not harmful to bees, but bees should not be sprayed directly. Actually, bees should not be sprayed with water, either. They don't fly around when it's raining because they need to keep their wings dry.

Spinosad

There's a bacteria product that only affects grasshoppers. You sprinkle it around. It doesn't affect anything else. One grasshopper gets infected and infects all the other grasshoppers in the area. Sorry, can't remember the name.

I think it's called Nolo. The grasshoppers spend part of their life cycle in the ground, and that is where they pick it up. It's pretty expensive, though. I saw it at Green Thumb.