Annual Control of the Oak Processionary Caterpillar

On Wednesday, June 14, the municipality of Voorschoten resumed its annual efforts to control the oak processionary caterpillar in public spaces. Unfortunately, the oak processionary caterpillar has been a recurring problem in recent years. From May through August, this hairy caterpillar settles in any oak tree it can find. The caterpillar’s hairs can cause irritation to the skin, eyes, and respiratory tract.

How do we control the caterpillar?

We take a proactive approach to controlling the oak processionary caterpillar. We follow these steps:

1. Risk Assessment and Documentation

We inspect all oak trees owned by the municipality of Voorschoten in advance for oak processionary caterpillar nests. If we find any nests, we mark the trees.

2. Control 

During the week of Monday, June 26, a specialized company will visit the marked trees to vacuum out the oak processionary caterpillar nests. Unlike burning or using poison, vacuuming is an environmentally friendly way to remove nests. This method does not harm other insects.

Report an oak processionary caterpillar

The oak processionary caterpillar lives only in oak trees. Its nest can be recognized by the white web. If you see an oak processionary caterpillar nest in an oak tree, please report it to the municipality as soon as possible by calling14071or using thereporting system at.