In nature, there is always a struggle for space and food. In this struggle, there are no winners. A biological equilibrium is established, where a beneficial fauna suppresses the reproduction rate of pests. And this pest, usually a polyphagous representative of the animal kingdom, can destroy large vegetable, grain, and fruit crops in a single day. On arable land, the real owners of gardens and orchards control this pest by their own methods. Here we present to you six of the most dangerous garden pests and how to deal with them.
The spider mite is a cosmopolitan and omnivorous pest
Among these Acari, the most common and best known is the Spider mite (Tetranychidae). Out of about 50,000 species, more than 1250 species occur worldwide, including Antarctica. Spider mites are tiny spider-like creatures. Males are 0.3-0.6 mm, and females up to 1.0 mm.
The body of Spider mite is round and covered with tiny bristles and sometimes tiny warts. The head has 2 pairs of eyes, and the mouthparts have suction. The legs have five parts. The color of the Spider mite body is variable, depending on the color of the main host. In most cases, Spider mite has red, green, brown, yellow-green, and dirty green colors.
By puncturing the tissue, Spider mite sucks out the cell contents.
Degree of the danger of Spider mite
Acari can destroy a plant in 3 days by acquiring it. The voraciousness of Spider mites, combined with their rapid reproduction (7 days from larva to adult), under optimal environmental conditions, causes epiphytic infestations on the leaves of green plants that never recover and must be destroyed.
To protect themselves from the environment, Spider mite weave their habitat (not all species) with fine spider webs. They live in groups under leaves and clods of soil. Eggs remain viable for up to five years.
Which crops are infested by Spider mites?
All Spider mite species are dangerous pests of garden and park crops. The pests colonize all plants, including flowering plants and houseplants. They are particularly attracted to all fruit trees, strawberries, beans, onions, jasmine, and roses. Flowering plants include begonias, gladioli, tulips, hyacinths, orchids, and others.
External manifestations of C. spider mite infestation
Yellow spots, small holes, silvery spots (cobwebs), discoloration, and leaf deformation (in bright light) can be seen on the leaves of infested plants. Spider mite infestation on plants is usually epiphytic.
Preventive, chemical, biological.
Systematic plant inspections are necessary to be able to save infected plants, especially indoor and outdoor plants. If a Spider mite infestation is suspected, treat plants (especially flowering crops) with insecticides or biological agents.
In cases where garden crops are heavily infested with Spider mite (30-35 days before harvest), naturally derived acaricides such as neem oil, pyrethrins, azadirachtin, and horticultural oils can be sprayed directly on adult mites, larvae, Rufus, and eggs to kill them at first touch. Spray on active spider mite infestations every 3 days until control is achieved.
Aphid (Aphidoidea) is one of the most common pests of green plants. Aphid is winged and wingless and has different functions in insect life. The body length of an aphid varies from 0.3-0.8 mm, while some species of aphid have a body length of 2-5 mm. aphid is oblong, ovoid, ellipsoidal, and hemispherical. The color of aphid varies from light green Aphid coloration varies from light green to green, yellow-green and black.
The body of Aphid is covered with hairs, tubercles, villi, and epiphytes. The small trapezoidal head is adorned with 2 red, brown, or black multifaceted black eyes. The forehead of the Aphid has long tentacles, which are organs of touch and hearing. The mouthparts are represented by distinctive proboscis that pierces the surface of leaves or shoots to suck plant sap. Aphid’s long, slender legs allow them to move by walking and jumping.
The danger level of Aphid
Despite their small size, aphids are vicious pests. Each female gives birth to 17 generations in the summer, giving birth to 100-300 new Aphids every 2 weeks. In the fall, Aphids sprout wings and repopulate new areas. They number about 4000 species in the taxonomy and are almost always carriers of viral plant diseases, over which the plant community currently has little control.
Which crops are affected by Aphid?
Aphid occurs in all vegetable and fruit crops as well as in flower beds. Weak or overfed plants that are susceptible to Aphid stings to produce nourishing sap are most often harmed.
Outward signs of Aphid infestation
The first sign of Aphid is the presence of ants on the plant. Ants disperse Aphid and feed on the sweet sap they secrete. On damaged plants, the young leaves at the end of stems and shoots curl. Over time, the well-developed older leaves become covered with a sticky coating that becomes a breeding ground for fungal and viral diseases. The leaves of some plants are deformed and form galls of various colors in which pests reside.
Methods of controlling Aphid
As with other pests, Aphid control methods are divided into agricultural, chemical, biological, and folk methods.
Using chemical methods to protect plants from aphids on small areas of private property is undesirable and hazardous to your health.
It is recommended to use biological agents that are not harmful to human and animal health. Insecticides (complexes of natural avermectins) and other biological agents. Aphid is completely eradicated within 1 to 3 days.
Neem oil, insecticidal soaps, and horticultural oils are effective against aphids.
Mole cricket is a member of the insect family Gryllotalpidae. Mole cricket is a large adult, 2-3inch (5-8cm) long, reddish-brown in color. The head of Mole cricket has a pair of large eyes and gnawing mouthparts.
The back has twisted wings in the form of flagella. They are used only in warm weather. The abdomen is tan and lighter in color than the back. Adults are capable of digging underground passages, crawling, flying, and swimming.
What crops are harmed by Mole cricket?
Mole cricket is one of the most dangerous pests, comparable to Grasshoppers and Colorado potato beetles in terms of damage to crops. A single adult can destroy up to 10-20 plants in a single day.
Adult and larval beetles feed on stems at the soil level and roots at the top of grains and vegetables, including eggplant, tomatoes, potatoes, peppers, cabbage, carrots, ornamental flowers, and shrubs. Adult Mole cricket preys on small insects, worms, and beetle larvae that live in the soil. At the same time, Mole cricket is known as “gourmets.” They do not actually use weeds as food, only edible plants.
Signs of Mole cricket destroying plants
Seedlings at the base of the stem are crushed, or shoots are bitten. The plant wilts within a few hours, start to dry out, and then dies. Plants damaged by adult Mole cricket and its larvae cannot be repaired and must be replanted with new plants.
On solid crops, gaps appear in the fields where one can find the nests of Mole cricket eggs in the middle. After rainfall, typical horizontal pathways made by adults can be observed around the plants and between the rows. The pathways usually lead to burrows with entrance holes varying in width from 0.6-0.8inch (1.5-2 cm).
Control measures for adults and larvae
All measures leading to the destruction of honey bee nests: deep plowing, systematic weed control, constant loosening of the soil – up to 6inch (15 cm) deep, trapping pits made of manure in autumn and spring, etc.
Soap solution is one of the simplest and easiest methods of control. Once you see the entrance to the mole crickets’ underground residence, prepare a soap solution and apply it directly to the hole with a stream. 1-2 liters of water will drive the insects out of the burrow. Then your job is to capture and eliminate it.
While sowing or planting crops, you can use Medvetox granular insecticide.’ Medvetox’ contains 50 grams of diazinon per 2.2 Lb (1 kg). The remaining ingredients are fillers, flavoring agents, and flavoring agents to attract pests.
It is an enteric and contact pesticide that can be used in agriculture and private home sites. The pellets do not become wet and do not dissolve in the soil. The bait is effective for 3 weeks from the date of insertion into the ground.
Liquid and granular formulations of insecticides are commonly used in the soil to suppress Mole cricket. In some cases, irrigation should follow the insecticide application because the insecticide must enter the plant’s root zone to be most effective, but this is an insecticide-specific requirement, so the insecticide label should be read carefully for application instructions.
Turnip moth (Agrotis segetum) is a particularly dangerous pest. Its inconspicuous appearance and modest size are deceptive. The body length is no more than 1-2inch (2.5-5cm). Turnip moth wings are monochromatic gray or yellowish-brown with individual spots and horizontal dark and light stripes. Female and male Turnip moths are dimorphic: females have grayish-brown hindwings, while males have white hindwings. Turnip moths are active at dusk and feed primarily at night.
Risk class of white-backed Turnip moth in winter
Under optimal environmental conditions, a female moth lays 600 to 2240 eggs, producing 95-98% of the caterpillars. Young moths emerge from the pupa 20-25 minutes after hatching and are ready to fly and feed.
Types of crops affected
Caterpillars of the Turnip moth damage more than 140 plant species in 36 families in winter. They are divided into leaf-feeding, intra-stem, and sub-stem and damage the root system of plants. Typically, the Turnip moth damages 10-20 sugar beetroots in a single day.
Turnip moth destroys roots of corn, tobacco, millet, and cotton. In summer, it attacks vegetable and technical crops, including squash, zucchini, peas, and potatoes; in fall, it invades winter and winter crops. Among weeds, the Turnip moth prefers to settle and feed on the roots of plantain, thistle, and creeper.
Signs of Turnip moth damage
Turnip moth caterpillars damage stems at the soil level and actually eat the bases of seedlings, potato tubers, and root crops, leaving characteristic cavities in which they sometimes settle. Turnip moth eats the soft parts of the leaves, leaving only the veins. You should be aware of the widespread wilting of plants over a large area in a single day.
Control measures for Turnip moth in winter
- Deep plowing and spring harrowing.
- Observe the return conditions of crop rotation.
- Complete elimination of weeds and systematic inter-row tillage of row crops.
The chemical control measures for Turnip moth, effective use of preparations Decis, Fas, Zeta-cypermethrin, etc. The chemical agents should be used at home with great care and strictly according to the time and dosage in the instructions.
Biological agents, such as Bitoxybacillin, should be used at home.
Melolontha is a dual pest
Melolontha is a large polyphagous pest. Adult insects reach a body length of 1.4-1.6inch (3.5-4 cm.) The body of Melolontha is light brown or tan. Flight and reproduction of Melolontha begin around the second decade of May. 1-1.5 months later, large white larvae with blackheads and mouthparts hatch from the eggs. Their white segmented bodies are coiled into the shape of an embryo.
Melolontha larvae live and feed in the soil for 3-4 years. By late summer of the fourth year, adult beetles emerge from their pupae and remain in the soil until spring. In spring, adult beetles begin to feed heavily on the ground. During this period, Melolontha is the most dangerous pest because the larvae in the soil damage the root system, and the surface beetles damage the flowers and vegetation.
Dangerousness of Melolontha
Melolontha populations increase significantly and rapidly under favorable conditions. The damage threshold for Melolontha is 1 larva per 11 square feet of area. Currently, there are 2-3 in some areas and more than 20 larvae per 11 square feet near forest strips. Thus, the threshold of harmfulness is repeatedly exceeded, i.e., it is possible to talk about the epiphytic reproduction of Melolontha.
Which crops are affected by Melolontha and its larvae?
Melolontha is one of the most dangerous pests. Both adults and larvae can damage plants. Adult Melolontha feeds on the leaves, flowers, and ovaries of all fruit and ornamental trees and shrubs during the flight and breeding seasons (about 1-2 months per year, mainly in spring).
Melolontha larvae gnaw on the roots of strawberries/strawberries, black and other currants, cherries, pears, apples (which they particularly like), poplars, birches, cedars, spruces, and other plants. In addition, the larvae of this pest become more and more voracious as they get older. Currently, there is a 10-year intensive breeding campaign of Melolontha and its migration to new locations. It is now necessary to take all measures to protect the plants and eradicate the pest.
Signs of Melolontha infestation
Plants infested with Melolontha destroy the leaves, flower buds, ovaries, and young needles of conifers. If the roots are damaged by the larvae, the plants lag in development, wilt, and are easily pulled out of the soil.
Methods of controlling Melolontha
Melolontha and its larvae cannot tolerate the odor and excrement of lupine and the nitrogen compounds in the soil. The number of Melolontha larvae per unit area can be reduced by sowing white clover, peas, and other nitrogen-fixing crops or by sowing mustard and cruciferous grass seedlings under yard pens.
During mass flights (late April through May), shake branches and collect Melolontha in the morning at temperatures no higher than 53-59°F (12-15°C).
The soil is covered with a fine ground cover in the form of shavings, crushed bark, chopped straw, chopped elder branches, chopped lupine pieces, various cruciferous plants up to cabbage leaves.
The following chemical preparations specifically targeting Melolontha larvae are recommended.
Zemlin, Actara et al – contact entericidal insecticide. Ammonia solution can be used as a harmless chemical agent to kill the larvae of Melolontha.
Nemabakt was developed based on soil nematodes. The biological product maintains a positive pest balance in the soil for more than 2 years. Kills pests within 3 days.
Biological agent Boverin etc., effectively kills larvae of Melolontha.
Grasshoppers – the hungry messengers
Asian Grasshoppers or Migratory Grasshoppers (Locusta migratoria). Every inhabitant associated with the green plant and animal world has seen Grasshoppers. Do you remember the story of the “green mare”? It is one of the 2 life forms of Grasshoppers, the solitary one.
Grasshoppers are large insects, 1-2inch (2.5-5 cm) long, similar to grasshoppers. They are characterized by a curved, sharp keel on the prothorax and a strong chin. The forewings of Grasshoppers have densely speckled with tan, and the hindwings are delicate and translucent, with a yellowish or sometimes greenish tinge. Depending on nutritional and environmental conditions, adult Grasshoppers may live solitary (green females) or gregarious (brown individuals) lives. In the solitary stage, Grasshoppers hardly cause any damage to the plant.
What are the dangers of Grasshoppers?
Grasshoppers are omnivorous pests whose feeding activity is concentrated in the early morning and late afternoon when there are no thermal peaks. During the swarming stage of Grasshoppers’ life, they form huge adult swarms (hopper swarms) consisting of groups of larvae. A swarm of Grasshoppers can eat 200-500 g of plants with different densities of plants and reproductive organs (leaves, flowers, shoots, stems, and fruits).
Grasshoppers devour everything on their way. A single group of Grasshoppers can occupy from 2 to 20 or even more thousands of hectares at a time, flying 186 miles (300 km) per day while feeding, and 621miles (1000 km) per day in the presence of a tailwind, leaving the bare ground and detached remains of woody shoots and plant stems in its wake.
Grasshoppers may survive in groups for several years, gradually fading and returning to a solitary life. The average interval between epiphytes is 10-12 years.
Grasshoppers control measures
- In areas prone to Grasshoppers, it is necessary to replant gardens or home plots in late fall.
- Deep harrowing in spring and early fall digging is recommended to promote damage to the nests (egg pods) of the pests.
- It is necessary to till unused areas, which will prevent the deposition of Grasshoppers’ eggs by ants.
Bait is a mixture of an attractive food source (such as wheat bran) and an insecticide. Common baits contain spores of methomyl (a carbamate insecticide) or locusts (a natural locust pathogen). Bait should be evenly distributed throughout the habitat and must be reapplied weekly and immediately after rain or irrigation. The baits are selective because they kill only grasshoppers and other foraging insects (N. locustae kills only grasshoppers).
The dust has a short residual and must be reapplied weekly and after rain or irrigation. Both baits and powders are easy to use but moderately expensive. A number of insecticide sprays are available to combat grasshoppers, including malathion, methomyl, permethrin, and bifenthrin. The insect growth regulator diflubenzuron (Dimilin) is available for commercial-scale applications.
Sprays are cheaper than baits and dust but require a sprayer appropriate for the scale of application. Sprays will kill on contact or when grasshoppers eat treated foliage. Check all product labels for permitted application sites. For example, some insecticides can be used on ornamentals but not on edible plants.
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