• Dipel is the commercial name of a biological insecticide produced by Valent Biosciences with the microorganism Bacillus thuringiensis subspecie Kurstaki. This insecticide is primarily used to control caterpillar infestation on crops, orchards and gardens. Dipel is biodegradable and there has not been any reported hazard to humans, bees, birds or aquatic creatures (as of October 2010).
  
  

Mode of Action

• Dipel has a specific mode of action. The caterpillars must ingest DiPel to die. When inside the caterpillar, Dipel causes stomach and blood poisoning within minutes. The larvae stop feeding in 30 minutes and die in a couple of days. Dipel is as effective as other chemical-based insecticides, but is not known to cause environmental damage. Dipel is certified by Organic Material Review Institute (OMRI) for use on organic crops.
  
  

EPA's Safety Requirements

• The U.S. Environmental Protection Agency (EPA) has granted minimum safety requirements for use with Dipel. According to Valent Biosciences, applicators are required by law to wear gloves, long sleeves and long trousers, as with any biological or chemical-based insecticides. People can reenter the treated fields four hours after application. Crops can be harvested the same day they are treated.
  
  

Application

• Dipel should be applied when larvae are young, before crop damage occurs. A spray of Dipel and water can be reapplied after usually three to 14 days, depending on larvae activity and quantity of rainfall after treating, among other factors. Dipel is found in different formulations, including Dipel DF (Dry Flowable) and Dipel ES (Emulsifiable Suspension). The insecticide can control more than 55 species of caterpillars, reports Valent Biosciences.