The cockchafer and the June beetle are closely related, with the June beetle only growing half the size. For many gardening enthusiasts, only the June beetle is considered a pest, as it spreads en masse and eats flowers and leaves in droves in autumn. However, the grubs, the larvae of the beetles, can also cause great damage. For this reason, both types of beetles should be controlled equally in order to nip the emergence of a plague in the bud. Biological measures are always preferable to chemical agents.
Cockchafer
The cockchafer belong to the leaf horn beetle family, which is named after the design of the antennae. The antennae lamellas contain up to 50,000 odor sensors, with these males detect females ready to reproduce during the mating season. With the occurrence in May there are often bare-eaten trees, but these usually recover and form new leaves with the Johannis shoot in June-July. The following aspects must be observed with the cockchafer:
- The last links of the feelers have lamellas that are widened in the shape of a leaf
- The cockchafer is most widespread in Central Europe
- Depending on the nutritional conditions, cockchafer can reach a body length of 2.5-3.0 cm
- Mainly flies in May and June, hence the name
- For the most part feeds on the leaves of deciduous trees
- Propagation by laying eggs in the ground
- Used as chicken feed in rural areas
- Cockchafer plagues often occur after longer cycles
June beetle
Just like the cockchafer, the June beetle belongs to the genus of the leaf horn beetle, but it is only half the size of its close relative. On warm evenings at dusk, the nocturnal beetles often fly through the garden and over the lawn. Especially in the very hot summer months with permanently high temperatures, the June beetle feels extremely comfortable, a fact that leads to mass reproduction in many places.
- June beetles reach a size of approx. 1.4-1.8 cm
- Yellowish to brownish body color, with light hair
- Are active from June to August
- Feeds mainly on leaves and flowers
- Females prefer to lay their eggs in the lawn
- Ideal conditions and temperatures lead to mass multiplication and plagues
- Serious damage to fruit trees and lawns, especially the roots, by eating
- Lawn shows dry and yellow spots
- Fruit trees can even die completely in the event of a plague
- Also attack rose bushes
Grubs
Both cockchafer and junior beetle reproduce by laying their eggs, from which larvae hatch. The beetle larvae are called grubs and spend their first years in the ground, although the length of time depends on the species. If the site conditions are right, mass reproductions can occur, from which large swarms emerge after the larval period, leading to an extreme one
Plague for humans and animals degenerate:- Cockchafer remain in the ground for 3-5 years
- This is followed by a complete metamorphosis into a sexually mature insect
- June beetle larvae live underground for two years
- These pupate in the spring of the third year
- Afterwards, the nocturnal June beetles hatch on warm and warm summer nights
- White grubs have no protection from UV radiation
- Eggs and larvae require soil with high humidity
- In the cycle of 30-45 years there is an enormous spread of the larvae
Biological measures
Chemical antidotes pollute the groundwater and harm not only animals but also human health. Therefore, preference should always be given to biological measures in order to work in harmony with nature. In addition, the harmful toxins and chemical casting agents are often not enough to get rid of the beetles and larvae. When it comes to biological measures, the gardener is on the safe side, especially when the garden is used to grow food:
- Setting up scent traps with attractants, available from specialist dealers
- Use of parasitic fungi to be spread on the lawn in midsummer
- Fungi grow into the larvae of the June beetle, causing them to die off quickly
- Fungus can survive for up to 15 years, during which time there is no more infestation
- Till the garden soil repeatedly from June to August
- Soil must dry well, with direct sunlight
- Eggs and larvae wither in the dry earth
Tip: As an alternative to milling, the use of a toothed cultivator creates a similar effect and lets the eggs and larvae die off relatively quickly.
Nematodes
When it comes to mass occurrence, the control of the beetles must be carried out more radically, but still from an ecological point of view. In this case, broods from nematodes are suitable:
- In extreme cases, use of nematodes
- Nematodes are roundworms that attack and kill the grubs
- The preparation can be purchased from specialist retailers
- Dilute the powder with water and apply immediately
- Use the product soon after purchase, as it has a limited shelf life
Tip: The nematode preparation can be used to reinforce the effect in wooden boards and then in the ground to attract the larvae and then lead them to death.
Prevent
Preventive measures can prevent the
Nip the infestation with the beetles in the bud and prevent the grubs from spreading in the long term. The garden remains intact and there are no poisons. These measures include, above all, the covering of the garden areas where the beetles often stay and want to lay their eggs there. The beetles that are under the cover can no longer take off and mating does not take place:- In summer, only water specific plants, leave large garden areas relatively dry
- Females look for other breeding sites because they prefer to lay their eggs in moist soil
- Spread plant protection nets over trees and bushes
- Cover the lawn area completely, for example with a garden fleece
- Apply covers just before dusk in the evening
- Penetration of the pests into the ground is no longer possible
- Females can no longer lay eggs in the turf
Natural predators
When it comes to fighting May and June beetles naturally, natural predators are one of the best ways to fight them. These were created by nature and are completely sufficient for a normal reproduction of the beetles:
- Targeted predators of the beetles
- These include bats, cats, moles, shrews, and birds
- Giving useful animals a new habitat
- Offer birds opportunities to nest
- Hang up bat boxes
- Lay out cat food and water bowls
Conclusion
Both the cockchafer and the June beetle can become a real nuisance in the garden if they are met with suitable conditions for nutrition and reproduction. Since the larvae stay in the ground as grubs for many years until they hatch, many gardeners are unaware of the impending danger for a long time. The nasty surprise follows after hatching, when the young beetles attack the trees and bushes in the garden, leaving the lawn wither and brownish discoloration. Biological measures, including scent traps, parasitic fungi, and tilling and cultivating the lawn, are of great help in combating the beetles. In extreme cases, it helps to bring out a nematode brood, special roundworms that kill the beetle. As a preventive measure, the lawn, trees and plants can be covered at dusk so that the beetles no longer have access. Natural predators are the best method of combating these nasty insects, as these ensure that their spread is constantly contained.