What are mealybugs?
The mealybugs They are insects that feed on the sap of plants. Specific, cling to the underside of leaves, often near the veins, as well as to the petiole (stem, usually green although it can be other colors, that joins the leaf with the branch or trunk) if there is one.
When are they most active?
They love the heat so we will have to be a little vigilant during the driest and warmest season of the year. If we live in a temperate region, that will be the summer, although depending on the area it will not be too much to inspect the plants in spring and / or autumn.
For example, where I live (Mallorca), both in April / May and in September the maximum temperatures are high, exceeding 20ºC, and that is something that these insects love. In fact, it's not uncommon for me to come across a cochineal cactus in early fall. Therefore, if the place where you live is hot, it is highly recommended to inspect your plants every day or every two days.
What are the most common types of mealybugs that affect plants?
Plants can be affected by various pests, and if we talk about mealybugs, the most common are the following:
Corrugated mealybug (Icerya purchasi)
Image - Flickr / José María Escolano
La corrugated mealybug It is an insect similar to the cottony mealybug, but differs from this for having a reddish-brown shell that keeps the body protected. It is oval in shape, and like all mealybugs, it can multiply in large numbers.
- Favorite plants: it is quite common in citrus (orange, lemon, mandarin, etc.).
- Symptoms: the fruits turn yellow and can be spoiled; affected leaves also lose color.
Cottony mealybug or cotonet (Planococcus citri)
Image - Wikimedia / Whitney Cranshaw
This is the easiest to identify. As the name suggests, the cottony mealybug looks like a small white cotton ball, and if it is pressed even gently it 'breaks'. Their eggs are reddish-orange in color, and are protected by cottony silks.
- Favorite plants: in general all, but attacks more citrus, ornamentals (including carnivores) and conifers. It will only appear if the plant in question shows any sign of weakness, which may or may not be visible to humans; That is, you may be thirsty, hot, and / or have some deficiency but have not yet manifested it externally.
- Symptoms: the leaves turn yellow and the fruits, if any, will fall off before ripening.
Red palm scale (Phoenicococcus marlatii)
If you have palm trees, you should know that they also "have" their particular cochineal: the red mealybug. It goes through three stages (egg, nymph and adult), and has a red body. Now, the female cannot move since her legs are stunted, so to protect itself secretes a white cottony liquid that is discolored.
- Favorite plants: palms and cycads.
- Symptoms: the leaves first turn yellow and then end up losing color, turning white. If the victim is a young specimen, without a trunk, it can cause death.
California red louse (Aonidiella aurantii)
Image - Wikimedia / VictorCegarra
El California red louse It is a type of mealybug that is nothing like the ones we have seen so far. It is rounded, almost flat, and is protected by a reddish shell.
- Favorite plants: citrus, palm trees and cacti, although it can affect others.
- Symptoms: yellowing of leaves and fruits, general weakening of the plant.
San José louse (Aspidiotus perniciosus)
Image - Screenshot of Agrocentrochile.cl
El san jose louse it is similar to the previous one: the female is about 2 millimeters in diameter, which is protected by a shell, and always lives attached to the plant. The adult male has two wings.