Catepillars are killing your plants - how can you get rid of them?

Bacillus thuringiensis or BT is a type of bacteria that's used to control the population of caterpillars. This natural pest control has been used by farmers and gardeners since the 1930s. Commercial preparations of the bacteria are still widely available today in feed stores and garden shops around the country. An alternative would be deltamethrin or permethrin dust.