Lightbrown apple moth		Greenheaded leafroller		Brownheaded leafroller

The bacterial spray Bacillus thuringiensis is widely used by organic growers for the control of leafrollers in fruit crops. It is available in various commercial formulations, such as Agree®, Delfin®, Dipel®, Thuricide®. These can be applied with conventional spray machinery. Leafroller caterpillars are highly susceptible to the bacterial toxin of B. thuringiensis, which destroys the larval gut, and they die within 2-4 days. The efficacy of B. thuringiensis on pipfruit is less than on some other crops, such as kiwifruit, probably because of more rapid degradation of the spray deposits by ultraviolet radiation and rainfall. With efficacy limited to 1-2 weeks in the field, control may require a series of spray applications. However, these can be timed in relation to the life cycle when caterpillars are present in greatest numbers. Pheromone trapping can be used to monitor leafroller populations and trap catches provide action thresholds for guiding spray decisions.

Bacillus thuringiensis is common in the environment, such as in soils and organic waste. However, this bacterium does not infect leafroller caterpillars naturally or provide natural control of leafroller populations.