Natural enemies are already adapted to the habitat and to the target pest, and their conservation can be simple and cost-effective.
Microbial pesticides can control many different kinds of pests, although each separate active ingredient is relatively specific for its target pest[s].
The Paradox of the Pesticides implies the need for more specialized pesticides that are tailored to the target pest.
In certain cases, however, where the predator is closely related to the target pest even narrow spectrum pesticides may be insufficient.
Bt corn can adversely affect non-target insects if they are closely related to the target pest, as is the case with Monarch butterfly.
The oils provide control by smothering the target pests, and are only effective if applied directly to the pest, and provide no residual controls.
Comparing the life histories of nematodes and target pests can often explain such failures (Gaugler et al. 1997).
Record-keeping is essential, as is a thorough knowledge of the behavior and reproductive cycles of target pests.
The main focus here is on promoting beneficial insects that eat target pests.
The beneficial insects reared in the laboratory are harmless to the environment; they attack only the target pest, ignoring plants, vegetables and other insects.