pests are organisms that are considered harmful to humans, their presence cause harm to humans and human activities. In other words they injure humans , desirable plants , animals and spread diseases. It's important to mention that the definition of a pest is a human invention , a pest is define from it's harmfulness to human interest for example , the Siam weed , edible grasshopper and elephant grass. When the plant or insect are important to human it is not considered a pest but when it is harmful it is considered a pest. E.g elephant grass used for feeding of animals like goats and cows is not a pest when looking at the point of view . But when the elephant grass grows on our field with our crops at that time it is considered a pest because the compete directly or indirectly with our crops. Types of pest.: 1) Insects , insects are athropodes ,jointed legs with 6 legs or 3pairs of legs e.g grasshopper. 2)weed ,. Weeds are plants that interfere with human activities or in some way intrude with human comfort and walefare e.g Siam weed. 3) Nematodes, Nematodes are small unsegmented work like organisms which are present in almost all agro ecosystem were They interact directly or indirectly with plants and other microfauna . 4) mollusk ,this are late group of animals of animals characterized by soft non segmented bodies , they may be aquatic or terestral and may not posse shells e.g snails and slugs . 5) vertebrate : A vertebrate is an animal with a spinal cord surrounded by cartilage or bone e.g rats ,grass cutters , some birds. 6)mites ,mites are insect like organisms with 8 legs ,these athropodes belong to the order Acarina e.g red spider mite . They are controlled by miticide....
