BE ALERT: The Pine Processionary Caterpillar

Spending Time in the Woodland? Beware of the Pine Processionary Caterpillar!

This year the pine processionary moth has undergone a population explosion and its caterpillars can be seen on pine trees in forested, open and urban areas. KKL-JNF experts provide some background information on the caterpillars and the necessity for precautions when coming into contact with them, as they can trigger allergic skin reactions.

Pine processionary caterpillar nest. Photo by KKL-JNF Photo ArchiveThe caterpillar of the pine processionary moth (Thaumetopoea pityocampa) lives in pine trees in woodlands, towns and residential communities. Physical contact with it can trigger an allergic reaction that can take the form of itching, a skin rash and/or a burning sensation in the eyes. Care must also be taken to avoid the caterpillars when they descend in procession from the trees between March and early May, in search of pupation sites.

As KKL-JNF is well aware that the general public is liable to come into contact with the caterpillars during woodland excursions, it takes the necessary annual measures to combat the problem. Special emphasis is placed on sites where large number of visitors congregate (such as recreation areas), their environs, and forests where especially large numbers of the caterpillars are to be found.

KKL-JNF foresters check for signs of the pest each year in November and sites are sprayed from the air in December, mainly with an environmentally-friendly biological formula that is harmless to human beings.

It is important to add here that it is impossible to predict the size of the caterpillar population for any given year, as its full extent does not become evident until around the beginning of January.

In 2016 the pine processionary caterpillar has been observed over a much greater area than in previous years – and hence, also, a greater number of people have come into contact with it. In response, KKL-JNF has doubled the area of woodland to be sprayed in comparison with previous years. Because of the unforeseeable population explosion and the narrow window of opportunity for spraying the young larvae in wintertime (which is limited by rain and wind), some forests have not yet been treated, while in others treatment has proved insufficient.

A pine tree destroyed by the Pine processionary moth. Photo by KKL-JNF Photo ArchiveKKL-JNF is continuing with complementary spraying of the pine processionary caterpillar wherever necessary at sites popular with the public, in order to ensure the safety of visitors to recreation areas.

We ask people to remain alert during the period between Purim and Independence Day:

  • Do not touch the caterpillars or their “tents” (i.e., their whitish fluffy-looking nests).
  • Do not linger under trees where pine processionary caterpillar nests can be seen.

Nonetheless, we invite you to continue to enjoy walks and picnics in KKL-JNF forests and woodlands. You need only remain alert and cautious.