text: what do locusts do to crops?   the  locust can increase extremely rapidly in numbers with the possibility of four generations through spring, summer, and autumn. it can form into dense aggregations (bands containing up to several thousand hoppers per square metre) as hoppers (the young locust before it can fly).the adults can form into swarms covering large areas and with upwards of 50 adults per square metre. they are formidable eating machines that can rapidly devastate crops. their preferred food source is green grass or clover or lucerne but they have been recorded eating green leaves from many different plants.the highly mobile nature of swarms and their ability to migrate over large distances means that virtually all agricultural areas are at risk from damage.