A good IPM farmer will inspect his/her fields regularly. During these visits to the field, sick plants (for example a virus infested plant) and infested leaves or branches should be removed and destroyed. By removing these infested plant parts (whether infested by insect pests or diseases), the source for further spreading is taken away. We call this “clean cultivation”.
Destroying the infested plant parts can be done by burning them, by burying them, by feeding them to farm animals or by using them for making compost.
Also the removal of debris under the plants (e.g. fallen leaves) can be useful in some situations as some pests pupate on the ground between this organic material. It should be noted however that this organic material also plays a role in maintaining populations of defenders. For example spiders may feed on the small insects that are present in the decomposing material.
When removing dead plant parts from the field, the farmer is removing nutrients and reducing the fertility of the soil. By using the leaves and branches for making compost, the farmer can compensate for this loss.
Another aspect of clean cultivation is the destruction of crop residues.