The Cochinilla del Carmin devastates prickly pears

This emblematic plant is a quintissential part of the Spanish landscape

The Cochinilla del Carmin is a well-established pest in the hotter areas of the Spanish coastline, slowly destroying the emblematic prickly pears which form part of the traditional Spanish landscape. These were cultivated for food, acted as hedges and also had important medicinal applications, and their presence is a sure sign of human habitation, many country fincas surrounded by great banks of prickly pear.

How to identify the Cochinilla del Carmin

The arrival of the Cochinilla del Carmin is easy to spot, the chumberas assuming a whitish hue, and within a short time white, fluffy splotches appear. It looks at first glance as though the plant has been spattered with white paint, the white splotches spreading across the plant at frightening speed, until the plant turns brown and dies, leaving a large clump of rotting plant material.

Examined closely, the splotches show a fluffy, thread-like appearance, and when prodded with a stick, appear to bleed, a sticky red substance adhering to the stick like candy floss,  leaving a gossamer thread when the stick is lifted away.

The red substance is the key to this pest, revealing it to be a relation of  the cultivated cochineal beetle used to manufacture cochineal dye, which appears in all manner of cosmetic, food and textile products, the same family as the scale insects which regularly show up on mimosas, citrus trees and ornamentals.

 This particular variety is called La Cochinilla del Carmin, wild cochinilla, Dactylopius, native of Central America.

There are many varieties of Dactylopius, the most famous being Dactylopius Coccus, which is cultivated extensively in the Canary Islands for cochineal extraction, whilst others are used as a biological control, but this particular pest, Dactylopius opuntiae, has no practical use and devastates prickly pears, which are the only plant on which it can survive.

The females have no wings and are incapable of flying, so lay their eggs beneath a protective, cottony layer, each female producing an average of 130 offspring during the 80 day period of her lifespan. The young excrete a sticky thread like substance, which is how the insect spreads so quickly, the wind picking them up and blowing them across onto other leaves, or carrying them some distance.

The males, meanwhile, can fly, and in areas of high infestation are a real nuisance to humans, behaving like mosquitos where they are attracted to the light. Swatting and crushing leaves red staining and it is particularly unpleasant when infestations occur near to swimming pools as they can colour the water giving it a blood-like appearance.

It must be stressed, however, that whilst they are a nuisance, they cannot bite like mosquitos, so cause no actual harm, other than leaving a red spatter, which often gives the wrongful impression that they have drawn blood. 

What to do if you have a problem with Cochinilla del Carmin

If the presence is minimal, rub off the cottony substance, and scrub with water and washing up liquid. As with other scale insect family members, washing up liquid breaks down the protection of the cottony mass, removes UVA protection, and the tiny insects hiding beneath the cotton mass are killed by the sunlight.

If the infestation is more widespread , spray with clorpirifos mixed with a little drop of olive oil, which helps it to stick to the insects.

As with all chemical spraying, protective clothing and eye protection should be worn and windy days avoided, or contract a professional. ( chemicals can be obtained from agricultural suppliers)

Affected plants may also be buried, but it is vital to clear all traces of the infestation and spray the ground around the plants with insecticide, as well as neighbouring plants. In large scale outbreaks, earth moving equipment is used to bury the clumps, as they can reach large sizes and cover vast areas when left to their own devices.

 Failure to treat will result in the destruction of the plants, as the feeding nymphs suck the plant dry.

This leaves an ugly, brown heap, which collapses and rots, attracting flies with a most unpleasant smell, so if you see signs of this infestation on prickly pears, act immediately otherwise it will spread across every plant in the vicinity and kill the lot.

If leaves are cut away to prevent rotting ( and buried) stumps will repsrout although it is advisable to continue teatment in order to minimise the risk of reinfection.

There is no public aid for owners with infested plants, so it is the responsibility of the land-owner to treat the infestation, hence its rapid spread as many simply don´t put any value on their plants and are reluctant to spend time or money treating them.

Although the Cochinilla is most active during warmer weather, it should still be treated immediately if spotted all year around to prevent its spread.

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