The Cochineal
Cochineal is a parasite that occurs in hot and dry climates. It feeds on the sap and weakens the plant.
To feed itself, the cochineal moves throughout the plant leaving a sticky trail that will alert us to its presence, where it acts silently both indoors and outdoors.
And the worst thing is that its secretions produce a fungus (called sooty mold) that destroys plant material. Here's everything you need to know about this unwanted insect.
Crop infestations appear when we least expect them and are very complicated to manage.
Cochineal, like aphids , is one of the most common as well as being among the most dangerous, in fact if we don't realize it it can ruin the cultivation at the least opportune moment.
These tiny parasites, with seven pairs of legs and two pairs of antennae (measuring from 1 mm to 1 cm) can appear in both indoor and outdoor cultivation , and only need heat and low humidity to present themselves.
Cochineal insects are characterized by having a kind of protective shield of different colors and consistencies, depending on the species in question, making them difficult to treat using insecticides. There are approximately 8,000 species of scale insects divided into various families, in particular in cannabis they are the cottony scale insect and the short citrus scale insect .
The cottony cochineal insect is normally gray and is covered with a silky and soft white substance which serves as protection for the eggs.
The low citrus cochineal , the protective shell and looks like a limpet vulgate but with a darker color .
However, both affect the aerial parts of plants and act in a similar way: they move along the plant in search of food by sucking the sap with their beaks, which partly expel a sugary secretion in the form of honeydew .
Can cochineal be prevented?
One of the ways in which cochineal reaches our crops is through other plants such as rose gardens, geraniums, or other ornamental plants that can be found nearby. Therefore, a safe distance between the different plants present is essential.
Furthermore, cochineal finds ideal conditions to grow in hot and dry environments. Preventing our cultivation from having these characteristics is essential to combat it and, obviously, it is advisable to always have good ventilation , especially if it is an indoor cultivation .
This infestation is much more frequent during hotter times of the year or when plants lack the necessary nutrients . Another way to prevent mealybugs is to coexist with one of its most effective natural predators: the ladybug .
Why is cochineal so dangerous?
Cochineal insects are not a particularly destructive species but the greatest danger lies in their rapid spread.
They reproduce quickly and the males can fly to fertilize the females, which are wingless, making the infestation spread quickly. The male flies in search of the female and, after reproduction, she lays her eggs in the plant on which he is found. It can lay between 300 and 500 eggs , even 2000 if the most favorable conditions arise.
From the hatching of the eggs a larva will be born which will transform into an adult in a few days. Their rapid development and fast growth mean that there can be several generations of cochineal in the same season, they nest especially under the leaves and form colonies between the branches.
How to identify cochineal to intervene on cultivation?
Usually, the scale insect initially attacks at the base of the branch, from which it will slowly rise to expand. It is necessary to pay attention to the lower area of the plant because it can give us some indications to know if our cultivation presents the first symptoms of cochineal. The yellowing of the leaves is a further indicator that will tell us that something is stealing its lifeblood.
The clearest sign of the presence of cochineal will be the sticky trail that the insect leaves when it moves. The cochineal crawls along the plant in search of the sap on which it feeds. As it moves, its gelatinous body secretes a slimy substance that penetrates the branch. Discovering this trail will signal to us that something in the plant is not right. In the case of the cottony cochineal, the silky tufts of the eggs reveal its existence to the naked eye. Touch the leaves to check if they are sticky. Furthermore, this honeydew released by scale insects creates an ideal habitat for other parasites such as the sooty mold fungus, which can darken the leaves and prevent photosynthesis.
Be careful! The presence of honeydew is not exclusive to cochineal. Aphids and whiteflies also leave this type of footprint that can mislead you. For this reason, noticing the insect among the branches will be the most infallible method to confirm that our cultivation is suffering from this infestation.
Ants can be another clue to the presence of cochineal in our cultivation. Ants are greedy for the honeydew released by aphids and scale insects when stimulated by the ants, having in return a defense from their natural predators.
How to intervene in a cochineal infestation?
Cochineal weakens our plant. For this reason, it is essential to act quickly when we notice its presence.
The first thing to do will be to isolate the plant or plants involved from our cultivation to avoid the expansion of the infestation, and obviously check those which in theory are healthy. From this point we can begin treatment.
Cochineal insects have a shell that serves as a shield to protect themselves from external attacks; for this reason the use of insecticides often does not guarantee their elimination.
Without a doubt, there are other alternatives which, in addition to being natural, will be very useful if our crop is in the flowering phase, a time when it is not convenient to use chemical pesticides on the leaves. The solutions that we can apply to the plant are:
Neem Oil . Use neem oil by spraying it on your plants, this natural deterrent is an excellent remedy.
A mixture of alcohol and soap. To prepare it, just dissolve a spoonful of liquid soap in a small amount of warm water. Below, we add a liter of water and (not necessarily) a spoonful of methyl alcohol and spray it on the plant.
Fern infusion. Prepare an infusion with a handful of fern leaves for each liter of water and it will fumigate on the plant. This method is mostly used on indoor plants.
A mixture of tobacco and soap. Dilute a spoonful of soap in 5 liters of water. Then add 6 tablespoons of tobacco. Mix well and fumigate the plant.
Oregano decoction. Macerate 3 tablespoons of dried oregano for each liter of water and leave to rest for 7 days. Filter and spray on the plant every two weeks.
Natural predators. It consists of using other insects that are enemies of the cochineal such as ladybugs or parasitic wasps.
Uses of Cochineal in history:
Their ability to proliferate has made it a very profitable insect throughout history, thanks to carmine red or cochineal red, one of the most used natural pigments and dyes in the world. The carmine scale insect (Dactylopius coccus) is a parasite of nopal, the symbolic cactus of Mexico.
From the dried and crushed body of this female cochineal, carminic acid is obtained, which acts as a red dye.
The value of this pigment was already known by the Aztecs before the arrival of the Spanish in America. When the Spanish conquered Mexico in 1521, they saw the natives collecting insects from the nopals using the deer's tails to detach them. This dye became known in Europe starting from the 16th century, where there was great interest since the Middle Ages in obtaining the perfect red pigment, becoming one of the most valuable Mexican export products for the Spanish Empire, surpassed only by gold .