Biological control of the oak processionary caterpillar
Wolterinck BV in Beltrum, the Netherlands, is a specialist in tree care and weed control and works on behalf of local authorities and governmental bodies. Co-owner and general director Ivo de Groot has witnessed the effect of Koppert’s nematode product Entonem on the oak processionary caterpillar. ‘We’ve been using nematodes for years. The product is our preferred method over products based on Bacillus thuringiensis, which can only be used on trees with leaves. Nematodes are a better solution for urban areas.’
Wolterinck BV sprays the nematodes when the caterpillar egg casings begin to emerge. A second spraying may be needed, either of nematodes or of nematodes plus Bacillus thuringiensis-based products. ‘That is effective around ten days in and if the trees have at least 30% of their leaf cover, Bacillus thuringiensis can also have a good combatting effect.’
Staunch advocate
Wolterinck BV is a staunch advocate of Entonem against the oak processionary caterpillar. Ivo de Groot continues, ‘The product has a guaranteed firm, preventive effect, it’s a 100% natural and it helps preserve biodiversity.’