BIOLOGICAL HAZARDS Biological hazards are of organic origin or conveyed by biological vectors, including pathogenic microorganisms, toxins and bioactive substances. Forest biodiversity is continuously threatened by the re-emergence of native pathogens and the arrival of new invasive forest pathogens. Invasive forest pathogens (IFPs) For the last 70 years, the consolidation of emerging production areas on the world market, the speed of transport, the removal of customs barriers, international tourism, and the decentralisation of production have led to a strong increase in the movement of people and goods at an international level, and consequently to the unintentional introduction of IFPs. Invasive forest pathogens are responsible for high economic losses and strong negative impacts in forest ecosystems. Ips typographus Examples of IFPs Here are some examples of IFPs which have recently affected our forests. The larvae of the ( ) are the main pests of pine and cedar forests, particularly in the Mediterranean area. The most obvious signs of the ’s presence are the nests formed by the caterpillars in January. Then they move in large numbers in and defoliate conifer trees, weakening them. Chemical control treatments are mainly applied by aerial spraying. pine processionary moth Thaumetopoea pityocampa moth 1 nose-to-tail processions severely The ( ) is an invasive species in chestnut forests and orchards in various parts of the world. Indigenous to China, ACGW spread first in Japan and then North America and, most recently, in north-western Italy. The caused by the wasp on buds, leaves, and can weaken sweet chestnut trees and result in tree Infestations in small chestnut orchards may be reduced by pruning and destroying the infested shoots. At present, a natural parasitoid ( ) can be used avoiding the adverse side-effects of pesticides. Asian chestnut gall wasp Dryocosmus kuriphilus galls petioles decline. Torymus sinensis The ( ) is a cylindrical, browncoloured insect, about five millimetres long, that is endangering Italian forests especially in the Alpine belt . The beetle digs intricate tunnels under the bark that interrupt the flow of sap particularly to trees, but also to and killing them within a few weeks. Any chemical spray application made after beetles have penetrated the bark may be ineffective. Chemical treatment must target the adults by spraying the bark so that beetles are killed when they attempt to into the bark to lay eggs. European spruce bark beetle Ips typographus 2 spruce larch, white spruce lodgepole pine, bore MORE Contact with the pine processionary is very dangerous both for humans and animals (in particular dogs and horses) as its urticating hairs (600,000 per caterpillar) can cause extreme itching, skin irritation and damage to eyes and the respiratory system. 1 MORE The invasion in the northeast of Italy was triggered by the presence of a large amount of wood still on the ground in the most inaccessible areas affected by Windstorm Vaia. This wood-killer insect began to reproduce at an increasingly worrisome rate, starting from the trunks on the ground and then infecting the plants still standing. 2