Worms are sucking insects from the order Homoptera proboscis (Homopter) of the suborder Coccidians, which also include the infamous scale insects and pseudo-scale insects. Since they develop and harm plants in a similar way, we will talk about the whole trinity at once. Usually, without going into the intricacies of species differences, in everyday life any worm is called “mealy”, based on the fact that adult females (they, as a rule, are first of all noticed on plants) are covered with white soft waxy secretions, as if insects were sprinkled with flour … Females are quite large – up to 1 cm, sometimes more.
Coccids. Farmer Burea-Uinsurance.com SB_Johnny
In our garden, “giant” nettle worms live on nettles, the wax tubes with which they are covered reach 2,5 cm. By the time of flowering, the stalks of the nettle are strewn with garlands of worms, but since they are not interested in other plants, we do not fight with them – let them help us get rid of nettles. It’s another matter if coccids appeared on indoor plants, then urgent measures must be taken.
Scales and false scutes are small insects with a protective coloration, so they are very difficult to notice on plants. They look like more or less convex swellings on the leaves (along the veins, on the petioles, in the axils), in other places on the plant.
Why are some shields and others false shields?
The shield of the former consists of wax secretions of an insect and many larval skins, which the larva sheds as it grows until it finally matures. Scabbards are rather flat and extremely difficult to detect.
False shields are more convex, their shields are of a different origin – their dorsal integuments are simply compacted, under which the female with eggs is located. In some species (cushion pads), the eggs are under a wax cushion on which a scale-like female sits on the side.
Insects reproduce quickly and, by sucking juices from plants, can cause their death. On adult females (some sit motionless, once and for the whole life sticking to the chosen place, others can move, but not quickly) no contact poisons act – the pests are protected by a shield. Therefore, systemic poisons are needed (Actellik, Rogor). These drugs penetrate the tissues of the plant, making their juice poisonous for a while, and the coccids, having sucked it, die. But females also have eggs under the shield, from which, even if the female dies, larvae can hatch, not so well protected, but very mobile, for which they received the name “vagabonds”.
As soon as they emerge from the eggs, the tramps spread throughout the plant. Some suck and begin to feed, overgrowing with a shield and developing into an adult insect, others are transferred to neighboring plants by the slightest breath of wind and even simply ascending air currents (for example, coming from heating batteries in winter). Thus, they can spread over long distances.
The fight against coccids has to be waged “on all fronts.” They need to be removed from the plants without waiting for the larvae to hatch, and often all plants in the house should be sprayed with contact insecticides to destroy the already crawling insects. There are a great many insecticides on sale, so I will not indicate the frequency of spraying and dosage – all this is in the instructions, do not forget to just ask the sellers for them.
But I do not advise relying solely on chemical treatments. Prevention is very important here. Plants on which coccids have been seen should be inspected as often as possible so as not to miss out on lurking and surviving pests.
About males coccids – a special conversation
In some species, coccids do not have them at all, these pests reproduce only parthenogenetically, that is, females lay unfertilized eggs, from which new females are hatched. In other species, males appear from time to time. But they do not live long – only in order to find and fertilize a female, they have no time to feed and have nothing to eat. Therefore, males do not directly harm the plants, but as individuals participating in reproduction, they are certainly undesirable. They, like little vagrants, can be “taken” by contact poisons.
Carefully examine each new plant brought into the house, not excluding bouquets of flowers. It is better to treat “Novoselov” with drugs against pests, just in case, or to hold it for at least 10 days (and in the cold season, when pests reproduce slower and longer) in an empty room, where there are no other plants. Or at least temporarily isolate the newbie by covering him with gauze or a plastic bag.
Keep oranges, apples and other fruits brought home in the refrigerator. Put only well-washed ones in a vase on the table, especially for citrus fruits: whole colonies of coccids sometimes nest on their rough skins.
No matter how much you would like to quickly attach a new acquisition to a permanent place and see how this plant will look among others, try to keep newcomers away from old-timers and inspect them several times a day. For example, I got citrus fruits, laurel, murraya, cacti, ficuses, orchids inhabited by coccids, but I managed to do without chemical treatments. In several steps, I found and destroyed all the pests by hand.
- I. Vladimirova