Before 1980, the oak processionary caterpillar was still rare and was only spotted a few times in our country. From 1987 onwards, the caterpillar became more common, especially in North Brabant and the adjacent part of Limburg. Reproduction increased from 1996 onwards and we now find the caterpillars in most provinces. Due to the favorable weather conditions, we find the animals in large numbers this year, making the nuisance more severe than last year. But what does the life cycle of the processionary caterpillar actually look like? And at what point do they pose the greatest danger? You can read all about it in this blog.
September – mid-April: overwintering eggs
During this period, the packets of eggs overwinter in the tops of the oak trees until the following spring.
Mid-April – mid-May: young caterpillars
The eggs hatch quite early in the spring, often before the oak trees grow leaves. Due to the high temperatures last year, the development of the processionary caterpillar is accelerated. The mild winter ensures that the eggs will hatch earlier this year. When the eggs hatch, the caterpillars are orange in color.
Mid-May – end of June: fully grown caterpillars
After the eggs have hatched, the larval stage lasts about 2-3 months, during which the young caterpillars molt a total of 5 times. During this period, the oak processionary caterpillars mature and become grey-grey in colour with light-coloured sides. After the third molt, they get both long and short hairs on their backs. The microscopic hairs have barbs and are poisonous, these are also called stinging hairs. Each caterpillar can have as many as 700,000. The hairs are repelled when threatened and easily penetrate the skin, eyes and respiratory tract via the wind. This can cause unpleasant complaints in humans and animals. Think of skin rashes, red eyes, swelling, itching and respiratory complaints.
During this period, the well-known behavior of the caterpillars can also be observed. They crawl in large numbers (in procession) from the branches to the leaves on which they feed at night. Currently, more oak trees are planted and therefore more caterpillars can stay alive. This also means that we will have to deal with more nuisance.
When the caterpillars have eaten their fill, they gather in compact nests. The nests are made on the trunks or branches of the trees and consist of threads, stinging hairs, droppings and molting skins. In very hot weather, the ground at the foot of oaks is also popular.
Mid-June – end of August: emerge
In July, the butterflies are fully grown, after which they develop into adult gray-colored butterflies. From the end of July to the end of August, the butterflies fledge, with the males going further than the females. The nests are left empty in the oak trees. Molting skins, pupa skins and stinging hairs remain in this. The stinging hairs retain their toxic substance for a long time, which is why the danger is not completely over.
August – mid-September: butterfly
The adult butterflies are nocturnal. They mate and produce egg packets with 20-50 pieces. These put the females in the crowns of different types of oak trees when they fledge. Young caterpillars will hatch from this next spring. Thus the cycle begins again.
Nuisance? Van der Velden fights within 24 hours!
The oak processionary caterpillar can be a nuisance for a long time, even when the butterflies have fledged. In addition, there will be more caterpillars in our country this year. To prevent unpleasant complaints, it is therefore important that you are alert to the presence of processionary caterpillars in your neighbourhood. Do you think you are suffering from a processionary caterpillar infestation? Do not hesitate and immediately call in Van der Velden Pest Control Service to combat them in a professional manner. We will contact you within 24 hours if you have a request. Please contact us via call me back. You can also reach us via the contact form. Request a quote, get the costs and make an appointment right away. We control processionary caterpillars in Amsterdam, Amersfoort, Amstelveen, Almere, Haarlem, IJmuiden, Hoofddorp, Uithoorn, Utrecht, ‘t Gooi and Zeist, among others. With Pest Control Service Van der Velden you will be free of pests again in no time!
