Pine Caterpillar (Procesionaria)- Information on the pest of the Mediterranean forests/ woods

I normally do not spend my time writing on bugs, this however is going to be an exception. Due to the lack of information in English (there is plenty in Spanish and Italian) on this issue, my civic side has come out and I would like to help any one with this problem. Today's theme is going to be the Thaumetopoea pityocampa (sometimes spelled Thaumatopoea pityocampa) or more commonly referred to as the pine processionary caterpillar or Procesionaria in Spanish. If you think the Latin name is ugly, then just wait to you meet this worm. As its name implies, the pine processionary caterpillar is a kind of caterpillar that lives on the tree tops of Pine Trees. The word processionary comes from the fact that they line-up forming long caterpillar lines that can reach several meters long, although generally they only measure around a meter. They live their joyful life in the forests of Spain, Italy, France, Northern Africa and other Mediterranean States.

Pine Catarpillar

H o w do I know that I have seen or been close to them ? If you had a nice walk in the woods and your skin itches or has irritations or ...it feels that a couple of insects have bitten you or ....your eyes irritate ...or if your dogs mouth's lips have started swelling or dribbling / foaming (may even leed to vomiting) or... if you see a long line of caterpillars on the road (hopefully very flat ones), floor or tree trunks, then yes -you have been unlucky enough to have met one of the Mediterranean's worst pests!

I myself, have seen them all my life and never had any problems with them. When small we just knew that they where “up to no good” things, that could blind you and like most children in this part of Spain, when you saw one you either left it or stepped on it. My problem with these pine processionaries started this past late March when after being close to the pine tree in my garden, a couple of hours later my skin would itch like if I where bitten several times by mosquitoes or flees.

The biological cycle of these Pine Processionaries starts in Summer when moths start popping up from the ground. These moths have been buried for most of the summer while they where in their cocoon stage. Incredible like it may seem, these creatures can be buried up to several years until they sense the best condition to resurrect. The moths dig themselves up during the night, find a male or female moth, mate and fly towards the most appetizing Pine tree in the hood, lay their eggs and die. Around four weeks later, the eggs start hatching. A couple of weeks later the bugs start getting nasty as they acquire an outer layer of thin hairy needles. These needles will serve as their defence mechanism and anytime they find themselves in danger, they will ex pulse these needles causing the previously mentioned irritation on their prey. The itching and irritation effect is caused by histamine on the needle tips (only visible on the caterpillar meaning if you see it, your are too close for comfort). The caterpillar themselves leave the nests at night, when they are less vulnerable to pray such as birds. They feed on different parts of the tree and make there way back to the nest before morning. These insects rarely leave their host tree until they are ready to find an adequate place for cocooning. This occurs normally in March – mid April and yes, this is the period were if you are reading this, you where bitten!

How to fight the Pine Processionary Getting rid of the Pine Processionaries is a difficult task. Governments in the Mediterranean region have spent millions in fighting these bugs and the results have not been as satisfactory as expected. The best time to fight them is when they are less vulnerable, i.e. when the first nests appear (end of summer). Nevertheless, the nests are also less visible during this time. An option is to try to fulminate the tree with triclorfon at 5% or piretrinas (personally I have never tried this option). More effectively, when the nest is first found, try to pull it down (by the branch) or inject gasoline in it. That should kill anything inside. If you have chosen the most sensible option of pulling the branch down carefully dispose of it in a plastic bag or when possible – burn them. Unfortunately these worms like heights, and most of the nests will be found close to tree tops. In these cases you wont have many options except trying to shoot it down with an air gun or more effectively with a rifle with a thin compacted lead cartridge. Many town-halls will also help you deal with the problem free of charge - so give them a call before hand explaining the problem. Again, their Spanish name is Processionaria.

Pine Tree Nest in Spain

Once Bitten:
Once bitten you will probably get a rash. There is not much you can do now, but according to the locals I have spoken with, there are a couple of steps that can help you. First thing to be done is to wash the area with warm water – if possible shower as you may have been “hit” in other areas. Change clothes as soon as possible as the insects “hairs” may still be there. Be aware that rashes will probably occur in areas with higher exposure such as the face and areas susceptible to movement such as neck and upper area part of arm and elbow. All Pharmacies also sell pills and cream that will drastically reduce itching. If you believe you have been hit in the eye go to your doctor. Finally, the level of reaction depends much on the individual- I only got a rash for a couple of days, another person I have spoken to was in hospital for 2 weeks because he was highly allergic to them.

Your Pet:
In this case, your pet probably means your dog as Cat's tend to be a bit more clever and cautious with these things. Unfortunately, the dog does not even need to have seen one of these pine worms. Dogs have a bad habit of licking the area where the pet caterpillars have passed- having similar consequences as if the dog had been chewing on them. As mentioned above, symptoms that your dog has been in close contact with these creatures are dribbling or foaming from the mouth, and/ or sever rashes close to the mouth and tongue. For dogs these creatures can be specially nasty as they can cause them to lose their tongue. This from what I understand, comes from the intense itching that the dog simply scratches his tongue out or that it simply (Tongue) dies. It is therefore recommended to act with total caution and call a veterinary, they will know what to do.

PROCESSIONARIAS KEYWORDS: Caterpillar, Tree worms, Pine trees, Forest, woods, nature, Costa del Sol, Andalucia, Spain, Italy, Greece, long lines of worms, Pests, Pest control, Mediterranean, sick dog, vet, insect