Processionary

1. Processionary
2. Processionary Caterpillar Circle

The caterpillar is called a pine processionary because it primarily lives in coniferous plants such as pine. And because they move in a serpentine fashion, the name 'processionary' was given to them as well. In the wild, they are mostly found on pine trees, but they exist in urban areas where pine and cedar trees exist. Adjective of, relating to, or characteristic of a procession. Of the nature of a procession; moving in an orderly or regular succession, sequence, or the like. Of a style, design, etc., customarily used in processions: processional regalia.

There are many insects that will make your garden their home.

Some are good, but some are bad and will do damage as they consume the plants in your garden.

One of the most insidious is the pine processionary caterpillar.

For coniferous plants, the pine processionary caterpillar is one of the biggest threats.

Not only to the plant, but also to the health of anyone who consumes the plant where this caterpillar has been.

The presence of this caterpillar is to be taken seriously as it a threat to plants, pets, and those living in your home.

So, to deal with this threat, it is important that you recognize them by sight, learn where they nest, and what to do to get rid of them from your garden.

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• 8 Tricks & Home Remedies to Get Rid of Pine Processionary

What is the Processionary?

The caterpillar is called a pine processionary because it primarily lives in coniferous plants such as pine.

And because they move in a serpentine fashion, the name 'processionary' was given to them as well.

In the wild, they are mostly found on pine trees, but they exist in urban areas where pine and cedar trees exist.

Their most distinctive feature is the long, stinging hairs that is the defense mechanism of this insect and allows it to move.

It is these hairs that cause a harmful reaction to humans and pets when they contact the caterpillar directly to the skin.

Such reactions need to be treated quickly when they occur.

You can also see their nests which are quite distinctive as they look like cotton candy in a tree.

The larvae are born sometime around September in the northern hemisphere and they move about until winter sets in.

Once that occurs, they bury themselves in the soil to create a cocoon from which they become butterflies in the spring.

But before they become butterflies, they are at their most dangerous in terms of being a threat to humans and pets.

It is why you need to know where they nest, so you can identify and eliminate them from your property.

Why and Where Do They Nest?

The cause of their appearance comes from the pine and cedar trees that they nest and call home.

What makes them dangerous is when such trees are near gardens that provide a food source.

Plus, if your area is experiencing high temperatures with little rain, they can appear in greater numbers as well.

When winter ends and spring begins, they often consume the different types of pine in their area.

Black pine is the most desired of food sources, but the caterpillars can also consume other pines as well.

This means that they can move about once they leave the nest and cause damage before they bury themselves in the ground.

Development stages

Processionary caterpillars usually develop in 4 different stages. These are egg, larva, chrysalis, and adult butterfly.

The nesting process begins normally in May when the butterflies will mate and leave their eggs in the trees.

After a month or a little more, the eggs hatch to reveal the caterpillars.

It takes another month before their stinging hairs grow on their bodies.

The nest itself provides shelter and protection for the caterpillars from the birds that normally would feast on them.

It also helps them survive the winter before they bury themselves in the ground to create cocoons.

From the cocoons spring the butterflies and the process starts all over again.

8 Tricks & Home Remedies to Get Rid of Pine Processionary

There are good reasons to get rid of the pine processionary caterpillars.

Many of the following methods are easy to employ, but you may have to be diligent in keeping them going until the menace is gone.

1- Bacillus Thuringiensis:

This is arguably the last option, but it is effective in destroying the caterpillars.

Bacillus Thuringiensis is a product you can find at nurseries that are used to poison the caterpillars as they consume their food source.

You'll need to apply the product once a week during the infestation season.

The upside is that this product when combined with other natural toxins will penetrate the plant.

So, when it is consumed by the caterpillar it will become poisoned and die.

The downside is that this process only works during the larvae stage.

Once the caterpillars become adults, the product is no longer effective.

2- Kill by Hand:

If you can reach the nest, you can kill the caterpillars directly.

It is best to use gloves and protection, so you do not contact the stinging hairs.

One simple way is to light the nest with a match or lighter as it is flammable, then put the fire out once it has destroyed the nest with a fire extinguisher.

Fire is a brutal, but effective method in killing the caterpillars.

3- Dig Up the Pupae:

You can identify the places where the pupae have dug holes in the ground to create their cocoons.

They are normally near the pine that they built their nest, usually within 15 feet.

Look for a mount of sand that is a couple of inches in diameter. Dig it up and you will find the pupae.

You can choose your method of disposal, but they need to be removed or destroyed so they do not become butterflies.

4- Pheromones:

You will need to obtain some synthetic pheromones and place them in traps.

When the male butterflies detect the pheromones, they will fly into the traps and die.

This will lower the population of the pine processional caterpillar considerably.

If you cannot obtain the synthetic pheromones, considering calling a pest control specialist who may have some as part of their supplies.

5- Predators:

These caterpillars have natural predators that you can introduce to your garden to help keep them away.

Some of the more prominent of those that prey on the pine processional caterpillar include the following.

• Ants
• Bats
• Blue and Coal Tit
• Cicadas
• Wasps

While cicadas and especially wasps may not be a desirable predator to have near your home, the blue and coal tit is a lovely bird that can be attracted to your home with the right feeder and home.

Keep in mind that you still have to deal with the nest so the birds and predators can get to the caterpillars.

6- Soap & Water:

This is one of the easiest methods of discouraging the caterpillars from feeding on your plants.

Create a mixture of soap and water and place it inside a spray bottle.

Spray the plants and pines with the mixture as that will discourage the caterpillars from entering.

You will need to spray every few days to ensure that the mixture does its job, but it will not affect the plants themselves.

7- Tobacco & Water:

Alternatively, you can take a pack of cigarettes and place them in boiling water.

If you smoke cigarettes, then the ashes will do as well.

Once boiled and cooled down, pour the mixture into a spray bottle and use it on your plants.

You only need a little of the mixture to work as too much may damage the plants.

Tobacco carries a strong scent that keeps the caterpillars away.

8- Water Trap:

This may be the simplest of all traps. Wrap a plastic container around the tree so that it can hold water on all sides.

Seal it at the bottom so the water does not leak out. When the caterpillars descend from their nests, they will get into the water and drown.

You may want to fish out the drowned caterpillars ever so often, but this is one of the most effective ways of keeping them from getting to your lawn.

Ideally, you'll want to use more than one method to get rid of the caterpillars.

A combination of soap and water combined with destroying the nests should keep the population down.

Plus, attracting natural predators to your yard will help destroy the remaining caterpillars.

Why is Processionary Dangerous for Humans and Pets?

Processionary is covered with small stinging hairs all over its body and this is what makes these bugs dangerous.

Although they do not sting, bite or puncture the skin, they can severely affect us with their simple contact.

Humans as well as pets can develop severe irritations and allergic reactions (like urticaria and even conjunctivitis) if they touch the larvae of the pine processionary.

Burning sensation, reddishness, rashes, and itching are few other symptoms that can also be caused due to these caterpillars.

And the sad part is this irritation can last for several weeks even after the treatment.

Particularly these oak processionary moths and caterpillars can be a sign of danger for your dogs and cats, if they ingest them by mistake.

This often happens when your pet strolls through areas that are surrounded by pine trees.

In any such circumstances, it's important to immediately take them to a veterinarian for quick treatment.

When to Call a Professional for Pine Processionary Caterpillars Removal?

If you have tried these methods and are still not having success, a professional pest control expert is the answer.

They have the knowledge, equipment, and products necessary to identify and destroy the caterpillar.

It is true that calling a pest control expert will cost money, but it will be worth it since the threat of the caterpillar exists to your plants, pets, and your family.

The pest control expert will inspect your property, locate and destroy the nests, and use poisons or other products to dissuade the return of the caterpillars.

Because their treatments are temporary, you will need to have the pest control expert return to your property every year.

However, you may mitigate that to a certain extent if you employ some of the methods listed above.

For example, if you only have a few pine or cedar trees, the water trap is a great way to keep the caterpillars from progressing to the ground.

The Conclusion

The pine processionary caterpillar is a dangerous insect to have in your yard.

They present a real threat to you, your family, your pets, and your plants.

Understanding how to deal with this threat will provide the protection needed to keep them off your property.

Share the post 'How to Eliminate Pine Processionary Caterpillars in Your Garden?'

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Why is Processionary Dangerous for Humans and Pets?

Processionary is covered with small stinging hairs all over its body and this is what makes these bugs dangerous.

Although they do not sting, bite or puncture the skin, they can severely affect us with their simple contact.

Humans as well as pets can develop severe irritations and allergic reactions (like urticaria and even conjunctivitis) if they touch the larvae of the pine processionary.

Burning sensation, reddishness, rashes, and itching are few other symptoms that can also be caused due to these caterpillars.

And the sad part is this irritation can last for several weeks even after the treatment.

Particularly these oak processionary moths and caterpillars can be a sign of danger for your dogs and cats, if they ingest them by mistake.

This often happens when your pet strolls through areas that are surrounded by pine trees.

In any such circumstances, it's important to immediately take them to a veterinarian for quick treatment.

When to Call a Professional for Pine Processionary Caterpillars Removal?

If you have tried these methods and are still not having success, a professional pest control expert is the answer.

They have the knowledge, equipment, and products necessary to identify and destroy the caterpillar.

It is true that calling a pest control expert will cost money, but it will be worth it since the threat of the caterpillar exists to your plants, pets, and your family.

The pest control expert will inspect your property, locate and destroy the nests, and use poisons or other products to dissuade the return of the caterpillars.

Because their treatments are temporary, you will need to have the pest control expert return to your property every year.

However, you may mitigate that to a certain extent if you employ some of the methods listed above.

For example, if you only have a few pine or cedar trees, the water trap is a great way to keep the caterpillars from progressing to the ground.

The Conclusion

The pine processionary caterpillar is a dangerous insect to have in your yard.

They present a real threat to you, your family, your pets, and your plants.

Understanding how to deal with this threat will provide the protection needed to keep them off your property.

Share the post 'How to Eliminate Pine Processionary Caterpillars in Your Garden?'

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Welcome to ProShieldPest.com. I am Tina Jones. I have been lately working as a pest removal professional in Winslow, Arizona. At present, I love to spend my time with my family as a retiree. Here I share all my knowledge and experiences to help people understand better how they can stop pests at their home without actually killing them. Hopefully, the information you will find here useful that can help in safeguarding your home! Read more

The pine processionary (Thaumetopoea pityocampa) is a moth of the subfamily Thaumetopoeinae in the family Notodontidae. The species was first described by Michael Denis and Ignaz Schiffermüller in 1775. Sometimes placed in the genus Traumatocampa, it is one of the most destructive species to pines and cedars in Central Asia, North Africa and the countries of southern Europe.^[1] The urticating hairs of the caterpillar larvae cause harmful reactions in humans and other mammals. The species is notable for the behaviour of its caterpillars, which overwinter in tent-like nests high in pine trees, and which proceed through the woods in nose-to-tail columns, protected by their severely irritating hairs,^[2] as described by the French entomologist Jean-Henri Fabre.

Life cycle[edit]

Though most pine processionary moths only live one year, some in high altitudes or more northern areas may survive for over two years. The adult moths lay their eggs near the tops of pine trees. After hatching, the larva eat pine needles while progressing through five stages of development. In order to maintain beneficial living conditions, silken nests are built over the winter. Around the beginning of April, the caterpillars leave the nests in the procession for which the species is known. They burrow underground and emerge at the end of summer.^[3] High numbers of adults are produced in years with a warm spring.^[4]

The eggs are laid in cylindrical bodies ranging from 4 to 5 cm (1.6 to 2.0 in) in length. The eggs are covered with scales which come from the female and mimic pine shoots.^[3]

The larva is a major forest pest, living communally in large 'tents', usually in pine trees but occasionally in cedar or larch, marching out at night in single file (hence the common name) to feed on the needles. There are often several such tents in a single tree. When they are ready to pupate, the larvae march in their usual fashion to the ground, where they disperse to pupate singly on or just below the surface.^[5]

Fabre conducted a famous study on the pine processionary caterpillar where a group of them followed head-to-tail in a circle around the rim of a flower pot; they continued marching in the circle for a week. He described the experiment in his 1916 book 'The Life of the Caterpillar'.^[6] The study has been cited innumerable times by inspirational and religious speakers who view it as a metaphor for blindly following a leader or for confusing activity with accomplishment. Fabre considered his caterpillars to be mindless automatons, trapped because they were pre-programmed to blindly follow trails, in this case the endless one that they had laid down around the circular rim of the pot. More recent studies, however, indicate that the caterpillars were actually physically trapped on the narrow rim of the pot, their feet unable to gain the secure purchase that would be needed to descend its steep, vertical walls.^[7][8] In one experiment, groups of processionary caterpillars of the same age as those observed by Fabre were placed on a flat table top and surrounded be a circular glass ring, 8 inches in diameter and 1 inch high. The caterpillars soon moved to the edge of the arena where they began to circle, one behind another. They were allowed to procession in this manner until they had a well established trail along the edge of the ring. The ring was then removed, freeing the caterpillars of any constraint to their activity other than their trail. The circular processions persisted for an average of just two minutes before the caterpillars marched off in a straight line. However, when circular trails were established in a similar manner by younger caterpillars they continued to circle for as long as 12 hours after the physical constraint was removed, a considerable time but far short of the seven days observed by Fabre.

The moth's pupal stage occurs in a white silken cocoon under soil. The pupae measure around 20 mm and are a pale brownish-yellow color that changes into a dark reddish brown.^[3]

As an adult, T. pityocampa has predominantly light brown forewings with brown markings. The moth's hindwings are white. Females have larger wingspans of 36 to 49 mm (1.4 to 1.9 in), compared to a male's 31 to 39 mm (1.2 to 1.5 in).^[3] Adults only live for a single day, when they mate and lay eggs. How far they are able to spread depends on how far the female is able to fly during her short time as an adult. Her average flying distance is 1.7 km (1.1 mi), with a maximum recorded of 10.5 km (6.5 mi). The species flies from May to July.^[9]

Shelter building[edit]

T. pityocampa is a highly social organism. Throughout its life cycle, a pine processionary will make several shelters. The first of these are flimsy and temporary, but in the third instar, they build a permanent nest. Once their permanent nest is built, the caterpillars become foragers staying in the vicinity of the nest. The nest has no openings, so caterpillars force themselves through the layers of the shelter. The waste from the larvae's diet accumulates at the bottom of the nest.^[5]

Impact of foraging[edit]

The pine processionary caterpillar is responsible for most of the defoliation of southern Europe.^[10] Although pines are most susceptible to the caterpillar, other conifer trees such as larches are also vulnerable. The caterpillars can completely defoliate trees if large quantities are present.^[11]

Midwinter foraging and thermoregulation[edit]

The biologist Terrence Fitzgerald has written, 'Colonies are active throughout the winter months. Activity records of colonies foraging in pine forests in mountainous regions near Barcelona, Spain, obtained with infrared activity monitors, show that the caterpillars leave their nests soon after sunset and travel to distant feeding sites on the branches of the host tree. There, they feed overnight then return to the nest at dawn.' The caterpillars have been observed foraging on the coldest nights and can move at sub-zero temperatures. The nests are positioned so that they can be warmed by the sun. The caterpillars rest during the day and the heat in the nest helps them to digest their food. When they emerge from their nests in late March, they are fully grown and leave their nest processing towards pupation sites in the ground.^[12]

Trail marking and processionary behaviour[edit]

The caterpillars lay down a pheromone trail from the tip of the abdomen as they advance over the branches of the host tree. Although the caterpillars also secrete silk and mark their pathways with the material, it plays little or no role in trail following. Most likely, silk helps the caterpillars grip on smooth plant surfaces. The caterpillars can distinguish old from new trails. Caterpillars preferentially follow trails marked by larger numbers of caterpillars. Trail marking enables the caterpillars to aggregate at feeding sites and allows them to find their way back to nest after feeding. When they move over the branches, caterpillars may travel head to tail in small groups or alone. In either case, they rely on the trail marker to find their way.^[5]

Lengthy processions are formed when fully grown caterpillars abandon their host tree in search of pupation sites, when as many as three hundred caterpillars may travel long distances from the natal tree looking for soft soil in which to bury themselves and form cocoons. During processions, stimuli from setae on the tip of the abdomen of the caterpillar in front serve to hold processions together, taking priority over the trail pheromone or silk. A caterpillar can readily be induced to follow a model made of a wooden dowel covered with the integument of the abdomen of a killed caterpillar.^[5]

Anti-predator defence[edit]

Towards the end of their larval development, pine processionary caterpillars are highly irritating to the skin. Contact with the hairs of the caterpillar can cause severe rashes (urticaria) and eye irritation. Some individuals may have an allergic reaction to the caterpillar's hairs.^[5][13] Fifth-stage larvae can eject hairs when threatened or stressed; the hairs, which have the form of harpoons, then penetrate and irritate all areas of exposed skin nearby with an urticating protein.^[14]Allergic reactions may follow in susceptible individuals on subsequent exposure to the hairs.^[5]

Natural controls[edit]

The pine processionary is an economic pest in coniferous forests in southern Europe. It is controlled to some extent by predators, parasites and viruses which attack the moth at many stages of its life cycle:^[14]

• Eggs are eaten by the orthopteran Ephippiger ephippiger.^[14]
• Larvae are eaten by birds such as great tit (Parus major) and great spotted cuckoo (Clamator glandarius).^[14]
• Larvae are parasitised by solitary wasps (Ichneumonidae, Braconidae) and some species of flies (Tachinidae).^[14]
• Pupae are eaten by hoopoes (Upupa epops).^[14]
• Adults are eaten by bats.^[14]
• Larvae may be infected by the processionary moth virus Smithiavirus pityocampae.^[14]

Artificial control[edit]

Efforts to control the pine processionary have included biological control using Bacillus thuringiensis, which is effective on eggs and first- or second-stage caterpillars (in September or October),^[15] or insecticides such as diflubenzuron, an insect growth regulator, which can be sprayed from aircraft.^[16] Monitoring can include the use of pheromone traps.^[15] Older methods used insecticides in oil, inserted directly into nests, or mechanical removal of nests.^[15]

References[edit]

1. ^Kerdelhué, Carole; Zane, Lorenzo; Simonato, Mauro; Salvato, Paola; Rousselet, Jérôme; Roques, Alain; Battisti, Andrea (2009). 'Quaternary history and contemporary patterns in a currently expanding species'. BMC Evolutionary Biology. 9 (1): 220. doi:10.1186/1471-2148-9-220. ISSN1471-2148. PMC2753568. PMID19732434.
2. ^'FMV'(PDF). Archived from the original(PDF) on 28 July 2007. Retrieved 21 June 2013.
3. ^ ^abcd'Pest profile: pine processionary moth'(PDF). Archived from the original(PDF) on 4 March 2016. Retrieved 2 July 2013.
4. ^Mestre, João. Forest Health and Climate Changes. Universidade de Trás-os-Montes is Alto Douro, 2012.
5. ^ ^abcdefFitzgerald, T. D. 'Social Caterpillars' http://web.cortland.edu/fitzgerald/
6. ^Fabre, J-H. The Life of the Caterpillar. (1916) Chapter III: The Procession.
7. ^Fitzgerald, T. D. 2003. 'The role of a trail pheromone in the foraging and processionary behavior of Thaumetopoea pityocampa'. Journal of Chemical Ecology. 12: 513-532
8. ^Fitzgerald, T. D. 2008. 'Lethal Fuzz'. Natural History Magazine. 177: 28-33.
9. ^Pine processionary moth - Tree pests and diseases - Forestry Commission
10. ^Li, S.; Daudin, J.J.; Piou, D.; Robinet, C.; Jactel, H. (9 June 2015). 'Periodicity and synchrony of pine processionary moth outbreaks in France'. Forest Ecology and Management. 354: 309–317. doi:10.1016/j.foreco.2015.05.023.
11. ^GB, Forestry Commission. 'Pine processionary moth - Tree pests and diseases'. www.forestry.gov.uk. Retrieved 1 March 2016.
12. ^Fitzgerald, T. D. 'Social Caterpillars' http://web.cortland.edu
13. ^'Fabre, J-H. (1916) 'The Life of the Caterpillar'. Chapter VI. The Pine Processionary: The Stinging Power'. Efabre.net. Archived from the original on 9 July 2013. Retrieved 8 May 2013.
14. ^ ^abcdefghBonnet, Catherine and Jean-Claude Martin and René Mazet (August–October 2008). 'La Processionnaire du Pin'(PDF). Stantari No. 14. INRA. pp. 29–33. Retrieved 29 December 2011.
15. ^ ^abcControl of the pine processionary
16. ^Treatment with growth regulators

External links[edit]

Processionary

• Kimber, Ian. '71.002 BF2021 Pine Processionary Thaumetopoea pityocampa ([Denis & Schiffermüller], 1775)'. UKMoths. Retrieved 4 July 2019.
• INRA website: Processionnaire du pin (in French)
• https://orugaprocesionaria.org/ (in Spanish)

Processionary Caterpillar Circle