The oak processionary is an insect. The caterpillars grow into moths. Each moth lays 200 to 300 eggs. These eggs then turn into larvae and then into caterpillars. By looking at the oak processionary, you can see that it has a lot of long white hairs. The long white hairs are not the ones that are dangerous, the invisible hairs to the human eyes under the white hairs are. The hairs are dangerous because they can cause serious rashes, inhaling problems and blindness. A girl had been cycling under infected trees and she reported that a stone came into one of her eyes. Her mother could not see anything let alone a stone. Her eye became swollen and inflamed. A general practitioner said that everything was fine and that there was nothing to worry about. The general practitioner gave her antibiotics. After using the antibiotics the problem only got worse. She visited an eye specialist. Although the eye specialist removed many hairs, now she only can see 40 percent of her original eyesight and that number is still dropping steadily.
The dangerous hairs are only two millimeters wide. When the caterpillar feels that the situation is dangerous, then the caterpillar will fire those dangerous hairs like a hedgehog does. The dangerous hairs can also come loose when the caterpillar dies. The hairs are transported by the wind because they are very light. In the Netherlands most of the oak trees are infected by the oak processionary. Most of the infected trees have several nests. An adult oak processionary has hundreds of millions of little dangerous hairs. The average oak tree has thousands of these caterpillars and that means that the average oak tree has billions of dangerous fire hairs. If you distribute the fire hairs evenly of just one of an average oak tree, each person in The Netherlands get hundreds of fire hairs.
It’s called the processionary because each night the caterpillars go out of their nests in procession searching for something to eat. In the Netherlands there often red ribbons around infected trees. The ribbons are supposed to caution the people there. The ribbons do not really prevent contact with the fire hairs because the hairs can be transported hundreds of meters to somewhere where the people do not see the tree at all. In The Netherlands there are about 944 million trees. You can see trees everywhere. Of that 944 million trees are millions oaks. The oak processionary is not even from The Netherlands, the caterpillar came originally from Southern Europe; it was transported here by trade. The oak processionary causes very big damage. This year England and Ireland are not going to buy the oak wood from The Netherlands.
When you sum up the extra health costs, the damage to the oak trees, the fact that The Netherlands lost its oak wood client and the costs of removing the oaks you can safely say the damage is not less than a couple of million euros. There were many problems reported to the general practitioners. The government tried to solve this problem by making a website called ‘eikenprocessierups.nu’. It was visited from 79 countries. The website says what to do when you live near an infected oak for example.
I think it is really strange that the municipality chooses to hire people to take away the caterpillars, which costs about a hundred euros a tree with a vacuum instead of spraying poison before the eggs actually come ou, which is much more cheap. I also think that we in The Netherlands have way too many oak trees. Removing them does not per se mean economical damage. If they cut down the oak trees and sell them and plant sugar maple trees, then they will get a lot of money for the oak trees and much more for the sugar of the maple trees. Then there is not any climate change; we have a win-win situation. There are some people who say that removing the caterpillars causes harm to the biodiversity. That is not true because there are a lot more than is normal even in the places where they originated from. I think that this situation clearly shows the downsides of trading. The oak processionary is not the only animal that migrated to The Netherlands by trade, special kinds of ants and korean tiger mosquitoes also immigrated.
Here you can read on the website the goverment made. It is in dutch.
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