Brandenburg districts warn of pine processionary caterpillar outbreak as danger shifts to ground level
Authorities in multiple districts have issued warnings after the Kiefernprozessionsspinner, a relative of the oak processionary caterpillar, appeared in large numbers. The species, active from July to August, poses a particular risk to dogs because its stinging hairs collect on the forest floor.
New caterpillar outbreak
The pine processionary caterpillar (Kiefernprozessionsspinner) is spreading through Brandenburg’s forests, hot on the heels of earlier mass outbreaks of the oak processionary caterpillar. Several rural districts have now urged walkers and dog owners to be careful, after long-haired larvae were seen in large numbers on both trees and the ground. The insect emerges later in the year than its oak-dwelling cousin, with the main risk period running from July through August.
Health risks for humans and dogs
The caterpillar’s fine, hair-like bristles are the real danger. Contact with them can provoke caterpillar dermatitis, a painful skin rash, and allergic symptoms in sensitive people. For dogs the threat is more acute. The nests of the pine processionary are frequently on or near the forest floor, and the stinging hairs disperse at ground level where animals sniff. Because dogs inhale large quantities of the bristles into their upper airways, the creature poses a serious respiratory hazard for them.
Where the caterpillar is appearing
The district of Ostprignitz-Ruppin reported a sharp increase in sightings around Neuruppin and called for heightened vigilance. Farther south, in the Teltow-Fläming district, the Amt Brück warned of a proliferation in the woodland communities of Borkheide and Borkwalde. In both clusters the caterpillars, which travel in long, chain-like processions (hence their name), were observed moving on the ground as well as in the trees.
How it differs from the oak processionary
While the oak processionary caterpillar remains on the host tree, the pine variety more often builds its nests at or below ground level and pupates directly in sandy soil. This behavioural difference spreads the irritating bristles across the forest floor, making them harder to avoid for people and pets. The danger calendar also differs: the main threat from the oak species runs from May to July, whereas the pine processionary is at its peak from July to August.
Past damage to Brandenburg’s forests
The caterpillars feed on pine needles. In outbreak years they can strip whole stands bare, especially in vast monocultures. Brandenburg’s forests are heavily dominated by pine, providing ideal conditions for the pest. Earlier mass infestations in the region have already led to large-scale defoliation, and authorities are watching nervously as the current generation matures.
Advice for visitors
The counties have not yet announced specific closures or treatment measures, but their unified message to forest visitors is caution. Dog walkers are being told to keep animals close and avoid areas where the ground is thick with needles or where the caterpillars’ tell-tale procession lines are visible. With the high summer season only just beginning, the warning is expected to stay in place at least until the end of August.
