In late May and June you can often seecurl of apple leaves and visible around delicate spider webs or very dense websThese symptoms can be caused by4 different pests attacking apple treesIn order to get rid of them effectively, it is worth learning to distinguish them and learn how to combat them.So what to do when we see such symptoms on an apple tree?
Curling of leaves and spider webs on the apple tree
Fig. © PoradnikOgrodniczy.pl
1. Aphids
We meet aphids most often, because they attack many garden plants in large numbers every year. They causeapple leaf curlWhen you straighten such a leaf, you will see that the underside of it is full of small, usually wingless insects.By sucking the sap from plant tissues, aphids cause the leaves to deform, curl, and give off a sticky slope, which makes apple leaves stickyAs a result of contamination with aphid feces, seed-like fungi can develop on the leaves , reminiscent of a black raid.
Along with aphids, ants often appear on plants, which feed on honeydew secreted by aphids (the presence of ants can be treated as a confirmation that we are dealing with aphids).The next guests will be ladybugs and their larvae (in the photo below), which feed on aphids, thus helping us to reduce the number of these pests
Exactlydue to ladybugs and other beneficial insects that eat aphids, we should think twice before applying insecticides against aphids Unfortunately, with insecticidal spraying, we destroy not only aphids but also beneficial insects.
The larva of the ladybug eating aphids
Fig. © PoradnikOgrodniczy.pl
That's why I suggesttry ecological sprays based on natural substancesIn garden shops we will get natural remedies for contact pests, such as Emulpar 940 EC or Agrocover. In both cases, the preparation creates a sticky coating under which the aphids are suffocated. I used them andthey effectively eliminate aphids, but they do not prevent the raids of subsequent groups of pests
Thereforespraying must be repeated every few days or after removing the aphids with the above-mentioned preparations, reach for another preparations based on garlic and onionsThe smell of these vegetables is hated by aphids. Such sprays are able to scare the aphids away for the next few days, until the smell fades away.They can be homemade garlic and onion extracts or potash soap with garlic bought in a garden store.
If these methods do not deal with aphids or there will be a lot of these pests, which requires quick and effective intervention, you can use chemical insecticides for aphids, such as Karate Zeon 050 CS or Deltam (formerly known as the name of Decis Ogród). Both are proven preparations with high efficiency, and the grace period (the time that must elapse from the last spraying to the fruit harvest) is only 7 days. Just remember to follow all the rules described on the label of the product and to spray outside the bees' flight hours, preferably in the evening. In this way, we will minimize the harmfulness of the spraying to these beneficial insects.
2. Apple tree tent
Ifapple leaves are surrounded by a dense web resembling cobwebs , it is a sign that apple trees have been attacked by an apple tent.It is a common apple pest whose caterpillars skeletonize the leaves, that is, eat the top peel and crumb without damaging the bottom peel. They can also eat entire leaves and even damage the fruit buds, which wilt and fall off. At the base of the leaves, mines filled with caterpillar droppings are visible.
In May and June you can often find clusters of caterpillars with a pale body with white dotsIn July, characteristic butterflies hatch whose first pair of wings is white and covered with black dots. The females of the tent lay eggs in deposits of a dozen or so pieces. In autumn, caterpillars hatch from them and overwinter under shields made of egg casings, and then go to feed again the next spring.
Spider webs formed by an apple tree tent and a close-up of the caterpillars hidden under the row
Fig. XenonX3, CC0, Wikimedia Commons
The control of the apple tree tent during the feeding of caterpillars , i.e. when the presence of this pest is most often found, is quite difficult, as contact agents such as Karate Zeon and Deltam do not they reach caterpillars hidden under a dense belt.This is a clever pest!
If the trees are small and there are few pests,it is worth removing the cobwebs with hidden caterpillars by handHowever, if it is too laborious, you need to reach for a systemic and deep-seated preparation, such as Mospilan 20 SP. This agent not only fights pests through contact with their bodies, but also penetrates plant tissues and is sucked out by insects by circulating in their juices. This waycan reach tent caterpillars hidden under the beamUnfortunately, the spraying efficiency may not be 100% either.
Therefore, if we have observed a tent on our apple trees, it is very importantto perform a preventive spray in the next year at the beginning of a pink apple bud , that is when the little caterpillars of the tent leave the egg plates and start their journey in search of young apple leaves. During this period, they are not yet hidden under the shank and can be easily combated with contact agents, such asDeltam.
3. Spider mites
Spider mites are tiny spiders that suck juice from leaves. Difficult to see with the naked eye. Most often we identify them by symptoms. As a result of punctures by spider mites,small light yellow spots appear on the leaves of the apple treeIf there are many spider mites, the spots may blend together until the entire leaf turns yellow, turns brown and falls off. You can also often seetiny, very delicate spider webs woven by these pestsFruit spider mites or hop spider mites can appear on apple trees. In addition to apple trees, spider mites can also be found on the leaves of plums and pears in the orchard, and in the whole garden - on many different plants.
Foraging spider mites and spider webs woven by them on potted plants
The development of spider mites is favored by drought and high temperatures This year we have such spring and there are plenty of spider mites in the gardens. In the fight against these pests, we can support ourselves with garlic and onion husk extracts, and from ready-made natural preparations, it is worth reaching for Emulpar 940 EC or Agricolle Target.
Unfortunately, the fight against spider mites is difficult, becauseat the same time on the apple tree there may be different development stages of these pests , and the above-described measures do not work on all stages. Therefore, if ecological measures are not enough, it is worth reaching forhighly effective in combating spider mitesNissorun Strong 250 SC. It controls all developmental stages of the spider mite, except for adults. It will be a perfect complement to previously performed spraying with ecological preparations.
Nissorun Strong 250 SC is sprayed only once during the growing season . One should also pay attention to the long grace period of up to 28 days. This means that spraying must not be carried out later than 4 weeks before the apples are harvested.
Anotheragent recommended against apple spider mitesisOrtus 05 SCIt fights all mobile development stages of spider mites, and therefore perfectly complements the spraying with the aforementioned Nissorun Strong preparation. An additional advantage of Ortus 05 SC is a slightly shorter grace period of 21 days.
The recommended dosage of Ortus 05 SC on apple treesis 12-15 ml per 10 liters of water. Spraying is performed after the presence of the pest has been identified. A maximum of 1 spraying may be carried out during the growing season.
In the next yearit is worth to start combating spider mites on apple trees and other plants in early spring , when there are no leaves on the trees. Thenwinter spider mite eggs can be destroyed with ecological spraying of oil preparationsYou can reach for the Emulpar 940 EC or Promanal 60 EC already mentioned in this article.
Emulpar, based on blackberry oil, can also be used for later spraying against spider mites, aphids and other pests. In the case of Promanal, however, we must remember that spraying with this agent is performed only in the leafless period, because the paraffin oil contained in it during the growing season often causes phytotoxicity symptoms.
4. Apple leaf rollers
In early spring, green caterpillars with dark heads can be seen on young leaves, flower buds and flowers. These arecaterpillars of the leaf rollers , which later contribute to the rolling of the leaves into a tube shape. The name of this group of pests comes from the characteristic appearance of the curled leaves. They can be found on apple trees, among others. Beetle tortrix, rose tortrix and retina tortrix.
Retinal tortrix - Adoxophyes orana
Fig. Jae-Cheon Sohn, CC BY-NC 3.0 US, Bugwood.org
The caterpillars of the rollers produce yarn that clumps leaves together to form loose rosettes. They can also scrape the crumb from the leaves, which creates characteristic openings in the leaf blades.After noticing the caterpillars of the leaf rollers on the apple treespray the biological preparation Lepinox Plus. It is an ecological agent, safe for the environment and harmless to beneficial insects. Ideal forfighting caterpillars on apple leavesin garden crops.
Rafał Okułowicz
