Tuesday, 24 January 2012

Why Would You Do That?

On Sunday I went down to the plan d'eau (recreation ground) to get rid of our bottles in the recycling bins (station de recyclage). They were piling up in the pantry, but it was also a good excuse to get down to the river and the ditches that flow into it from the plan d'eau. With the mild weather, things could be happening much earlier than expected.

I particularly wanted to check on the caddis fly larvae that live in the ditches. They trundle about on the bottom in their ramshackle owner-built houses of grit and plant material and are a lot of fun to watch through the crystal clear water. There was also the possibility of toad spawn in long necklaces attached to underwater plants. Normally I would wait until February to check for this, but this year, who knows. Anyway, no toad eggs, but the caddis fly larvae were active.

A pile of Pine Processionary nests dumped in a ditch.
Where one of the ditches flows into the Claise I noticed there was quite a bit of sludge and plant material, but what caught my eye was a large hairy caterpillar. I realised that someone had dumped a load of pine tree clippings into the ditch. Each of the clippings had a processional caterpillar nest encasing it, and it was clear that it was these nests the culprit was trying to get rid of, not the pine clippings per se. It seemed like a peculiar choice of disposal methods, since the perpetrator must have had to bundle them up and carry them down to the river somehow. Why not pile them up and burn them? That is the standard method of destroying them. Why risk spreading the highly irritant hairs all over yourself and maybe even your car upholstery? My greatest fear is that they were first doused with insecticide which is now merrily washing down the Claise. Yohann, the river technician, is going to be more than a bit exasperated when he finds out.

One of the rather handsome caterpillars can be seen centre left.
Neil, over on Chez Charnizay, noted in a recent post that the processional caterpillars have been active all winter. They will indeed have been having a very easy time of it in the mild weather, but nothing except the very coldest weather slows them down. They are one of the climate change winners, moving inexorably up through France, further and further north. They are a real problem if, like Neil and Antoinette, you have pine trees in your garden. The nests are high up and you need a cherry picker to reach them to cut them down. The glass fibre like hairs float down, landing on your pets or the ground or your outdoor furniture. They produce a reaction that ranges from mild discomfort (similar to stinging nettle) to anaphylactic shock. Some people are more sensitive than others, and dogs are more sensitive than cats to the irritant protein the hairs inject.

Be careful if you see the nests in trees or the caterpillars on the ground and if you have them in your garden please dispose of them sensibly (by burning or pouring boiling water over them, taking care not to inhale the hairs, washing your clothes and indulging in a hot shower immediately after doing any nest pruning). For more details and photographs of Pine Processionary caterpillars, please go to our other blog, Loire Valley Nature.

Susan

6 comments:

Colin and Elizabeth said...

We had ten nests in one of our pines. These were carefully cut down and burned.All but one which we cannot get to... will try and catch the procession in a trap...

Susan said...

C&E: Just pour boiling water over the procession. That does for 'em, and means the hairs don't float in the air too much.

Jean said...

These caterpillars are a real worry for us, as there are several nests in the trees behind the château where we walk Lulu.

Maybe this was the work of an amateur - some well-meaning person who didn't really know what they were doing.

melinda said...

yikes those things sound scary.....are they in the US too?

Niall & Antoinette said...

arrgh! Just reading your post makes me start to itch again! We shall have the kettle at the ready once it is warm enough to sit outside. Antoinette

GaynorB said...

I haven't ever seen them 'in the flesh', but will look out for them!
Thanks for the advice.