Entomology is the study of insects. Entomologists, the persons who study insects, observe, sample, rear and experiment with insects. Research undertaken by entomologists covers the total range of disciplines with a biological connotation and includes ecology, evolution, behavior and anatomy. Biologists work with insects for many reasons, such as simplicity of maintaining laboratory cultures, rapid reproduction tempo and population turnover and high population numbers.

An entomologist involved in plant health is a scientist who studies:
*  the trophic structure of insects associated with plants
*  the effect of phytophagous insects on plant growth, yield and quality
*  the value of beneficial insects in pest management
*  the ability of phytophagous insects to act as disease vectors
*  the tri-angular interaction between insect pests, their host plants and the environment
*  the integration of pest management strategies to prevent or minimize pests attacking plants

Insects may dominate food webs through their sheer volume and numbers and they have the ability to occupy diverse niches. Small size, growth through metamorphosis and trophic structure, amongst others, are the reasons for this success.  Feeding specializations in different insect groups include ingestion of detritus, rotting materials, living or dead wood and fungi, as well as filter feeding and phytophagy (which includes chewing and sap sucking), predation and parasitism. Insects may be aquatic, terrestrial or soil-living during part of or their entire lives and their life-styles may be solitary, gregarious, sub-social or highly social, whilst they may be day or night living. Insect life cycles can be simple or complex, allowing survival under a wide range of conditions, such as extremes of heat, cold, wet and dry.  Insects are only pests from an anthropocentric point of view and as such impact on the welfare, aesthetics and profits of man. Insects also benefit mankind by providing food and materials for use. Insects are also essential in ecosystem functioning, such as nutrient recycling, plant propagation (through pollination and seed dispersal) and maintenance of general community structure. Thus, through their vast numbers, the influence of insects on the environment, i.e. the living space of humans, is highly significant.  

In South Africa, entomologists working on plant related matters are employed by private (e.g. seed or chemical companies) or public institutions involved in environmental assessment, agriculture, horticulture, forestry, seed production or pesticide development.

By studying the full Entomology curriculum offered by the Department of Zoology & Entomology, Faculty of Natural & Agricultural Sciences, at the UFS. Persons interested in insects on plants can supplement their training by studying selected modules offered in the Faculty of Natural & Agricultural Sciences, such as Plant Pathology, Plant Breeding, Soil Science and Agronomy.