Thousands of pine trees in northern Italy that provide much of the country's pesto are being destroyed because of parasites that have no known treatment.
Italian authorities have been fighting the Matsucoccus feytaudi insect, which is red-brown in colour, since it arrived from France during the 70s, but it has made its way south into Tuscany where it is combining with two more species of parasitic beetle to ravage entire pine forests.
In the medieval town of Grosseto in southern Tuscany, authorities have earmarked 900 pines that must be felled to stop the spread of the insects.
Among the trees are stone pines, whose nuts are used in pesto. The decline in pine nuts has resulted in a sharp increase in wholesale prices.
Giuseppe Monaci, in charge of public contracts at the local council in Grosseto, said it was almost impossible to eradicate the insects: "We can do absolutely nothing except slow down the progress of the disease."
