Pine Processionary Caterpillars [version 2026]

General Discussion
1

As these dangerous pests were mentioned on the forum a short while ago (if only I had a quid for every failed search on here) I decided to take action. First I did a search of all the pines in the forest where Jules and I walk twice a day. Surprisingly, almost none in the forest beyond our fence, but through it and into the new area I bought last year there are a couple. But what shocked me was that there are at least half a dozen in my own garden. :astonished_face:

At this time of year they are easily spotted as the only greenery up top, apart from those trees with ivy growing up them, also easily spotted.

I then carefully scanned all the pine trunks for nests, again, before the leaves return, quite easy to see and thankfully saw no sign at all, But I will keep looking as they are not so easily seen on the ground and I have a dog whose nose seems permanently attached to Mother Earth.

If I see any it will be the ecopieges for me, no shotguns allowed in this neck of the woods. :wink: :joy:

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2

I had to do a google for this but it seems a good way to get rid of the little buggers. We have a couple of trees at the lake that we keep an eye on. Fortunately there is no sign of them but we’re always on the lookout.

Don’t go climbing up any of your trees David. I’ll be watching you! :eye:

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3

Don’t worry, I definitely do not like heights, not quite as bad as my mate in England who swears he gets a nose bleed on a shag pile carpet, but not far off and these ones are between 60 and 80 feet high.

Very relaxing down on the ground on the chair I leave there for the purpose, watching them swaying gently in the silent breeze, and doing my nest watch duties at the same time. :smiley:

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4

We were walking on the lane by our house a couple of weeks ago and saw what we thought was a six foot snake on the ground. As we got closer we saw it was six feet of lots of caterpillars all head to toe marching slowly. An old guy on his promenade told us how dangerous they are for dogs and don’t kick them. Since then we have seen so many but none as big or as wide as that initial sighting. Thought we were safe moving away from alligators and copperheads in the USA to Provence but these and the Oleander bushes have been interesting start to life here.

5

They love Scots Pines! Here in Portugal, there are not to many this year due to the wet winter we’ve had. Normally, you can see them marching across the road. They are blind, so hang on to each other nose to tail.( how sweet!) :scream::dog: If you see a nest, and you can reach it, a can of airspray will lock them in. You can also put sticky tape or gunk around the trunk of the tree they will climb down. I am well aware of these little killers. I have several friends in Spain who have lost their cats, and various parts of their dogs’ anatomy. ( tongue, nose etc) They are capable of shooting out the spines/ hairs from their bodies when agitatad. Be warned! Report to the Mairie any nests you see à toute de suite! They can deal with them hopefully. More people need to be aware of the offspring of the harmless little Silk Moth! By the way, there is an Oak tree version as well! Excellentes n’est-ce pas!

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6

Although if you have these nests in your trees and are legally obliged to deal with them, nobody seems to do anything.

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7

Indeed. Our neighbour left a Scots pine for a few years while the caterpillars did their worst and the tree became ill. When he eventually had it treated there must have been a couple of dozen nests. We stayed in all morning and kept the dog in until the men had finished, in case there were hairs flying around.

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8

I did that about a whole load of nests in the pine forestry around here and the response was the typical shrug and ‘yes we know, so what’.

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9

Well my favourite neighbours are Mario and Marie-Paul. Mario is a retired pompier, their younger son is a pompier and the eldest son is a pompier in Paris, thus a professional under the military, so the whole family is steeped in the danger.

I mentioned it the other day to them and pointed out the danger to dogs and the reply was swift ‘to us too’.

So, pretty sure a report by me will not fall on deaf ears. :joy:

10

Change the Maire at the next election!! Ours got all the branches containing ethe nests cut off, and burned them. These things are deadly to kids as well, tell them!

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Two things get in the way of that. First, I don’t get to vote and second it was in a neighbouring commune anyway. He’s also a very good Maire, as is ours.

Edit: I think at least part of the problem is that it’s planted pine forestry to be harvested for wood and whoever owns or manages it isn’t bothered about it. It could be that the Maire has no power to do anything.

12

To adults too, the very first time I saw them I knew nothing about them but fortunately decided to watch instead of intervening. They marched in a long column towards the gate, but then, instead of continuing under it, climbed up and over it and down the other side. No. 1 must have been one hair short of a brush and the rest of them very trusting. :rofl:

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13

These things can decimate a pine forest. As they have done in the Mimizan area. When they are on the march however, they are only looking to burrow underground to pupate. The silk moth is totally harmless. Its kids are a different matter. My mates cat lost her tongue after chewing on one of these caterpillars.

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14

Good morningI thought that I’d update, re-write, reinform y’all with regard to Pine Processionary Caterpillars/Moth (PPC)/(PPM) as the topic was running high elsewhere.

People are reporting this year that there seem to be more PPC cocoons and processions this year than other years. Many insects are affected by seasonal changes; so annual fluctuations are not unusual.

PPC

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APP3D Moon PPC
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As you can see, they are covered in hairs. That’s not the problem and they cause no risk if left undisturbed. The problem arises when, along their body, they have little black stripes, these are actually pouches which contain the toxic (urticant) hairs. If you disturb a caterpillar, the pouches will open and the hairs will be ejected, ‘porcupine-esque style’ to protect itself. That’s why they are a particular risk to dogs and children, who love to play with these fluffy critters.

Moths and butterflies are fully motamorphic; egg, larvae, pupa adult. Unlike semi-metamorphic which is egg, -adult with several moults, but always resemble the finished article (bed bugs cockroaches for example)

Lifecycle (approx) they seem to be getting earlier every few years as we’re all getting hotter.

Moth: emerges from the ground May-July, they fly about with sexual intent and lay their eggs on pine trees. Not all pine trees are liked, I’m sure that there is a list of trees they eat and don’t.

When the eggs hatch, the caterpillars, who are nocturnal, start to munch on the freshest pine needles. From August you will begin to see fluffy cotton wall buds appear, which will grow until the end of the year. The buds are a silken ball woven by the PPC, which could contain several hundred caterpillars. From august until December, the caterpillars will moult 4 times, from the 4th moult the caterpillars no longer feed.

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From about February to April, the caterpillars will begin to descend in procession; the leading caterpillar is female, followed by a head to tail procession of males ( I do not know how many females are in a cocoon, so I can’t answer that question!). The PPC will bury themselves into the ground to pupate to re-emerge as a moth to begin the cycle all over again.

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chopped out cocoon

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EcopiĂšge full of caterpillars

flame thrown cat’s

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EcopiĂšge

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PPC about to bury themselves

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Flame thrown cat’s

So, Cocoons in trees, it is rare that a Mairie will intervene, as at this stage, the caterpillars are a phyto problem, in as much that they are not deemed a risk to humans or dogs. However, cocoons can be treated with a dilution of Bacillus thuringiensis (Bt) a natural bacteria sprayed directly onto trees, the PPC ingest whilst eating the pine needles. -s ineffective after the 4th moult, see above, or the cocoons can be lopped from trees and burned.

Treatment timings:

PPM May-August sexual pheromone traps to catch as many male moths as possible.

September - November Spray treatment with Bt or cut and burn

December-Feb Cut only,

Feb-and of May EcopiĂšges to catch the caterpillars on descent.

Caterpillars on the ground can be burned using a flame-weeder.

So, in answer to questions via a different post; Cut and burn cocoons, yes, but try and avoid forest fires, you won’t be popular and you could get on BFMTV.

EcopiĂšges are excellent, or bird boxes, tits and sparrows can feed their brooding chicks up to 500 caterpillars a day.

Risks, Dogs and children wanting to eat them. Keep them well away. Cats aren’t usually interested in caterpillars.

Ecopiùges are expensive (from 30€ up, so mairies will say it’s down to you.

Cutting them out of trees, gloves, goddles, dust mask, long sleeves and trousers are required highly recommended.

You also have to bear in mind, the hairs can be carried on the wind, so if you are cutting them out, be aware of wind direction and don’t chop if you are next to a school and the kiddlets are out in the playground.

Bonne dimanche!

It is worth noting that only humans and dogs must be protestec against biocide products, Tiddles the cat and the pet canary are do not have the same cover of legal protection, but every effort should be mabe to ensure safe use on products.

I hope this helps!

Edit: Photos stored on One Drive are “.heic” files I had to convert them to “.jpeg” via an online converter.

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15

Not necessarily - our local town mayor is very good at making sure the traps in our local parks are installed each year.

Thanks Rob, very useful.

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16

Thanks for a very interesting and thorough discussion.

For your info, I’m putting this link onto both threads. Mairies should be aware of the dangers, what they can or can’t do.. as well as advising those who contact them re these little wrigglers.

EDIT: I saw some nests this morning, when returning home. Tomorrow I shall be speaking with staff at our Mairie and will report back.

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Many thanks Rob!..superbly written and all well understood.

..now, where’s my flame thrower :slight_smile:

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18

Since the Decree dated 27th April 2022 all Mairies have been well aware of these nasty caterpillars and correct procedures.

This link dated 25th March 2026 has useful info

I saw some nests this morning and will be discussing with my Mairie tomorrow
 I’ll report back.

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Yes, from me too, but why is it that the birds who feed on them aren’t affected?

As I have said elsewhere, I have at least a dozen majestic pines, I think it might have been a plantation many years ago before the house was built.

This morning as usual I got a bit of a neck ache because I visited every one and gazed up carefully to make sure my over view from the high point was correct. It was, there are no signs though a few splashes of sunlight through the canopy did make me look from different points to make sure.

My 2 favourites go straight as a die for at least 80 feet and I spend some minutes admiring them.

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20

We have 4 trees that have had nests. We have put up Ecopiege traps for the last couple of years and the number of “nests” have reduced each year.

2 years ago my wife was very badly effected by the caterpillar hairs and suffered for a coulee of weeks - since then the caterpillars are my enemy and I will do whatever to eliminate them.

We proactively cut down the “nests” that are not too high.

We have also scattered bird boxes around the garden in the hope some of the birds will eat the caterpillars.

In April I will burn the bags from the traps.

@Rob_le_Pest - do you think the pheromone traps work for the moths? I put one up in each tree last year but they didn’t seem to catch any.

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