FAO releases guide on how to protect forests from invasive insects
United Nation’s (UN) Food and Agriculture Organization (FAO) has released a guidelines on how to protect forest from invasive insects, which incurs billions worth of damages to forest every year.
FAO said its new guide to the classical biological control of insect pests in planted and natural forests distills information in a clear and concise way to assist forest managers in developing countries develop effective pest-control programs.
Bugs such as the Winter moth and Asian Chestnut gall wasp are the bane of valuable trees and the people who rely on and benefit from them.
Insect pests damage around 35 million hectares of forest each year, with particularly catastrophic impacts recorded when non-native species arrive in ecosystems where they have no natural enemies. The scale of impact is increasing with growing international trade and the effects of climate change.
“Fortunately, over the last decades, the global community has accumulated considerable knowledge on the application of biological pest control. The introduction of natural enemies of invasive species from their country of origin has proven an effective tool to combat their expansion,” FAO said.
As cited in FAO’s guide, Hiroto Mitsugi, assistant director-general of FAO’s Forestry Department, said classical biological control is a well-tried, cost effective approach to the management of invasive pest species.
For example, the introducing of Torymus sinensis, a parasitoid specific to the Asian chestnut gall wasp in China – which spread over Europe and decreased wood yields by 40 percent and nut yields by over 80 percent – proved effective, spreading on its own and killing more than three-fourths of the targeted galls, while leaving other native wasps alone.
The introduction of two parasitoids to the European winter moth – which during the early 20th century went on to ravage North America’s oak forests and cherry and apple orchard with tree mortality rates as high as 40 percent – have also collaborated to contain the pest, one particularly effective during outbreaks and the other a persistent predator at lower densities.
“Classical biological control does not eradicate an invasive pest species, but works to establish a permanent, self-sustaining populatiuon of natural enemies that will disperse and suppress a pest poplation or reduce the speed at which it spreads. When successful, it enables reductions in the use of insecticides, with corollary benefits for human and environmental health,” FAO further said.