5 May 1986 Entomology academics publish book on pest control

Using an approach called integrated pest management home gardeners and small farmers should be able to
achieve better plants, fruit and crops, according to book just published by two Lincoln College entomologists.

Titled Natural Pest Control, the book is by Professor David Penman and Mr Bruce Chapman, both of the department
of entomology at the college.

The soft-cover 115-page book is simply written, and is well illustrated with both photographs and line drawings. 

Professor Penman said the emphasis of the book was on non-chemical methods of pest control, using an ecological approach.

The book deals with biological control, cultural control, attractants and repellents, plant resistance and crop diversity, and insecticides.

These all lead up to discussion of integrated pest management or IPM - and how to develop IPM
 programs.

IPM uses a combination of techniques to control the many pests that threaten crops.

But cultural methods, resistant crop cultivars, attractants and pesticides are all used when needed.

IPM is an ecologically-based way of controlling pests, relying heavily on natural mortality.

Control tactics are sought out to disrupt as little as possible mortality factors such as natural enemies and weather.

IPM is an approach to pest control, not a control method in itself.

If control methods need to be used, compatible measures should be taken that will have little or no effect on natural mortality.

IPM does not rule out using pesticides and are as much part of IPM as other measures.

Before IPM is used, the book suggests building up information on the crops, identifying the pests, looking at environmental factors, and selecting control methods.

Then control methods are drawn up in the order that these may be used the book calls this a decision tree.

The selectivity and efficiency of each method has to be considered.

A method that controls pests, with little effect on other insects, such as predators, parasites and bees, is highly selective.

Selectivity can be desirable, but can be a disadvantage if there are several pests on a crop.

The book has tables ranking the control methods in order of selectivity and efficiency.

Other tables show compatibility with other methods, speed of action, and the duration of effectiveness.

The authors warn that simplicity is a spray ; IPM is much more complex, easily disrupted, and may take up to three years
before coming into balance.

As well as informative tables and diagrams, the book lists the trade names of chemicals, has a worthwhile glossary and indicates further reading.

This is a book that should be read thoroughly cover-to-cover, and then used as a handbook.

Natural Pest Control is published in New Zealand by Reed Methuen, of Auckland.

Professor Penman is the head of the entomology department, and Mr Chapman a senior lecturer in entomology.

Further information from Professor David Penman, Professor of Entomology, Lincoln College 8150, New Zealand ; phone (03) 252-811 extension 715.