The pine processionary, also known as Thaumetopoea Pityocampa, is a “procession” of several caterpillars which wiggle their way down trees between December and April, winding their way into soil loose enough to burrow.  

This tiny insect, in the larval stage, can turn out to be extremely dangerous for dogs and humans alike, especially if you spend a lot of time outside.


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Why are pine processionary caterpillars so dangerous?

In winter, caterpillars gather in ball-like nests in the branches of pines and cedars, weakening them greatly. They are covered in highly poisonous hair, which can cause serious allergic reactions, rashes, eye irritation and breathing difficulties.

pine processionary

Between December and April the caterpillars depart their nests in a procession, and wind their way to a soil loose enough to burrow. Keep on the lookout for these little critters slithering in line; they’re likely to catch the eye of young children or your pooch. 

If the nests fall to the ground, dogs tend to be drawn by their cotton ball-like shape and get closer to investigate. Every year, vets see numerous cases of doggos suffering from violent allergic reactions to these nasty little bugs, which can sometimes be fatal.

pine processionary

Symptoms include a swelling of the snout and tongue, which can turn purply-blue. If you see this, act fast by cleansing the dog’s muzzle with warm water (though make sure not to rub!), and head to an emergency vet clinic as soon as possible. The vet will give your dog powerful corticosteroids which should treat the allergic reaction quickly.


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