Integrated forest management of hylobius

 

This programme started in 1999 with the objectives of promoting and co-ordinating research into methods of “integrated crop management” in forestry as “integrated forest management” (IFM).  The general objectives are to enable:

• adoption of forest management methods that achieve acceptable levels of protection against pests and weeds with lower levels of chemical usage than at present;
• a reduction in the use of synthetic chemicals in British forests.

Within this general remit, the programme has rapidly focussed on the potential for IFM methods to minimise the current emphasis on insecticide applications to reduce damage to transplants from feeding by Hylobius abietis the principal forestry restocking pest.  In an extension to the well-established Integrated Pest Management approach, research is aimed at improving our understanding of the behaviour and population dynamics of the weevil.  Using this knowledge and its expected outcomes, managers will eventually be able to monitor populations to determine risks, so that appropriate action – silvicultural, chemical or biological – can be taken to minimise damage.  With these objectives in mind a series of major experiments started in 2003 to develop a Management Support System (MSS) to test the validity of existing information and to refine its application. The ultimate aim is to reduce populations below the economic threshold for a given site but initially the work will allow forest managers to make more informed decisions to improve restocking practices. Part of the IFM approach is to explore the potential for utilising natural variation in resistance of Sitka spruce to Hylobius to improve the quality of transplants in relation to their ability to withstand feeding damage.

A further major element to the programme is to develop a biological control method using nematode worms to kill Hylobius breeding in the bark of stumps.  Although they are applied specifically to conifer stumps, nematode worms are the same species that occur naturally in soil and are widely used in horticultural systems to control a range of soil-living pests. The technique is proven in small-scale trials and has given good levels of weevil population reduction in forest-scale trials.  The emphasis will now gradually move away from research experiments to larger forest scale trials linked to management support.  Recognising that chemical protection is likely to remain a part of the strategy for managing Hylobius, research is also maintained (though at a declining level) on proving the efficacy of insecticides.

Scientists in the programme team keep a watching brief for opportunities to develop IFM methods for other pests and diseases and to integrate with forest management initiatives such as Continuous Cover Forestry.  Close links will be maintained with researchers in other programmes where pesticide reduction and IFM methods are under investigation

The main outputs from this programme are advice to forest managers on control of Hylobius and advice to the Forestry Commission on control policies for forest pests.  The Management Support System for Hylobius will be a major development and the programme will be reviewed in 2005/06 after three years operation of the system.

Progress reports

Annual summary of research

Commissioned reports

No reports available at this time