Annual Control of the Oak Processionary Caterpillar

The municipality of Voorschoten will start the annual control of the oak processionary caterpillar in public spaces on Thursday, June 23. In recent years, the oak processionary caterpillar has become a recurring problem in Voorschoten. Almost no oak tree is left alone by the hairy caterpillar from May through August. The caterpillar's hairs cause discomfort and irritation to the skin, eyes, and respiratory tract.

How do we control the caterpillar?

As of 2022, the municipality of Voorschoten is committed to the proactive control of the oak processionary caterpillar. The following steps are taken in this process:

1. Risk assessment and registration

Ahead of time, all oak trees owned by the Municipality of Voorschoten are checked for nests of the oak processionary caterpillar. These trees are registered, and if nests are found, the trees are marked.

2. Control 

The marked trees are visited within a week by a specialized company that vacuum-extracts the nests of the oak processionary caterpillar.

We opt for an approach to the oak processionary caterpillar that is as natural as possible. We actively combat them by vacuuming the nests. Burning or using poison is also a possibility, but those are options we do not employ. In this way, we combat them in an environmentally friendly manner so that other insects are not harmed.

Report oak processionary caterpillar

The oak processionary caterpillar lives exclusively in oak trees. The nest can be recognized by the white webbing. Do you see a nest of the oak processionary caterpillar in an oak tree? Please report this to the municipality as soon as possible via telephone number 14071 or via the reporting system.