What’s a pesticide?

Pesticides are toxic chemicals designed, as the name suggests, to kill “pests”: any living thing which can damage crops. Pesticides include several categories:insecticides are designed to kill insects; herbicides kill weeds, and so on.

sorry. Thanks, but this is a charity site and upgrading from 1.5 is not going to be straightforward when they have no web dev budget, have a heart!