Guidebook aims to stop spread of ‘alien’ forest pests

Outbreaks of forest-damaging pests exacerbated by climate change and growing global trade

10 November, 2011/Rome -  A new guide published by the UN Food and Agriculture Organization (FAO) aims to help countries prevent forest-damaging pests from spreading to new areas.

"Due to climate change, previously inhospitable sites can become suitable for ‘alien' pests that are accidentally transported through international trade in wood products, seeds or nursery plants — as well as trade in other commodities packaged with wood materials," said Eduardo Rojas-Briales, FAO's Assistant Director-General for Forestry.

"The guide provides suggestions on how to reduce the risk of pest spread and to implement effective pest management strategies at every step of the forest commodities chain," he added.

Between 1992 and 2008, the volume of wood products traded internationally surged by 125 percent.

Meanwhile, at least 35 million hectares of forest are damaged by outbreaks of forest insect pests each year.

The UN agency presented its Guide to implementation of phytosanitary standards in forestry today at the Second Asia-Pacific Forestry Week in Beijing.

Warmer temperatures pose risks

In addition to globalization, global warming also factors into the spread of forest pests.

Increases in summer temperature generally accelerate the reproductive capacity of insects, while warmer winter temperatures improve their chances of surviving winters.

For example, in western Canada successive years of mild winters have improved the winter survival rates of the mountain pine beetle (Dendroctonus ponderosae). Infestations in British Columbia (BC) are now at epidemic proportions and causing massive destruction of pines — the pest has affected an estimated 17.5 million hectares and killed 726 million cubic metres of timber since the early 1990s, according to the BC Ministry of Forests, Lands and Natural Resource Operations.

Drought conditions associated with warmer temperatures have also weakened the trees and increased their susceptibility to the beetles. Warmer temperatures have thus opened up previously climatically unsuitable mature pine stands to the pest.

Practical solutions

Coping with such threats requires action on several fronts. Careful surveillance, the management of forest stands throughout the growing cycle and improved nursery, harvest and transport operations are important.

Given the large volume of wood products moving across national borders, implementing international phytosanitary standards helps ensure the safe movement of forest commodities from one country to another while aiming to minimise any restrictions on trade.

The FAO guide was authored by an international group of 100 scientists and phytosanitary experts from 46 countries and is intended for policy-makers, planners, managers and educators as well as forest workers who implement policies at the ground level.

It is currently available in four languages: Chinese, English, French, and Russian. Spanish and Arabic versions are expected to be published next year.

FAO and its partners are now focusing on strengthening country capacity to implement the guide.

Photo: ©Dion Manastyrski - Ministry of Forests, Lands and Natural Resource Operations, British Colombia
An outbreak of mountain pine beetles in British Columbia is causing massive destruction of pines.