What is the relationship between the economic injury level (EIL) and the action threshold (AT)?

The economic injury level (EIL) is the lowest population density of a pest that will cause economic damage, meaning that below this level, the cost of managing the pest would exceed the financial damages caused by the pest itself. The action threshold (AT), on the other hand, is a predetermined level of pest density at which control measures need to be implemented to prevent reaching the EIL.

The correct relationship is that the action threshold is set lower than the economic injury level. This provides a buffer, allowing for timely intervention before the economic damage occurs. By having the action threshold lower than the EIL, it allows for the implementation of management strategies to prevent pest populations from reaching levels that would result in economic harm. This proactive approach is essential in integrated pest management (IPM) to minimize economic losses while effectively managing pest populations.