Locusts are a serious pest to farmers and have caused a lot of damage all over the world. Locusts are in the order Orthoptera along with crickets, grasshoppers and katydids. Locusts are grasshoppers that migrate. They eat a huge assortment of plants. A locust can eat its own weight in food every day. Swarms of locust eat fields of crops until there is nothing left. They then leave looking for more food.