<P> The pine processionary ( Thaumetopoea pityocampa ) is a moth of the family Thaumetopoeidae . Sometimes placed in the genus Traumatocampa , it is one of the most destructive species to pines and cedars in Central Asia , North Africa and the countries of southern Europe . The urticating hairs of the caterpillar larvae cause harmful reactions in humans and other mammals . The species is notable for the behaviour of its caterpillars , which overwinter in tent - like nests high in pine trees , and which proceed through the woods in nose - to - tail columns , protected by their severely irritating hairs , as described by the French entomologist Jean - Henri Fabre . </P>
<P> The pine processionary ( Thaumetopoea pityocampa ) is a moth of the family Thaumetopoeidae . Sometimes placed in the genus Traumatocampa , it is one of the most destructive species to pines and cedars in Central Asia , North Africa and the countries of southern Europe . The urticating hairs of the caterpillar larvae cause harmful reactions in humans and other mammals . The species is notable for the behaviour of its caterpillars , which overwinter in tent - like nests high in pine trees , and which proceed through the woods in nose - to - tail columns , protected by their severely irritating hairs , as described by the French entomologist Jean - Henri Fabre . </P>
caterpillars that follow each other in a line
caterpillars that follow each other in a line
pine processionary ( Thaumetopoea pityocampa )
pine processionary ( Thaumetopoea pityocampa )