The Content Of The Article:
- What does the cherry fruit fly look like?
- How do maggots get into the cherries?
- Cover tree pulley in time with fleece
- Protective nets prevent oviposition
- Yellow sheets reduce infestation pressure
- Early varieties are spared
- Beneficials - valuable help in combating combat
- Biocide - last rescue with high infestation pressure
In the cultivation of sweet cherries in the home garden, the control of cherry fruit fly has top priority. The native pest infects the ripening fruits with maggots, so that in the worst case the entire crop is inedible. Home gardeners are not defenseless against the nefarious activity of this type of drill fly. This guide will familiarize you with ecological control methods for a maggot-free cherry enjoyment.
What does the cherry fruit fly look like?The significant appearance makes it easier for home gardeners to reliably identify the cherry fruit fly. The following optical attributes make a Rhagoletis cerasi distinctive:
- Body drawing: shiny black with yellow dots on the thorax and head
- Wing: transparent with blue-black cross bands
- Body length: 3.5 to 5 mm
- Eyes: green compound eyes
How do maggots get into the cherries?The disaster takes its course from the beginning / middle of May. At this time, the cherry fruit flies hatch after spending the winter in the shelter of the earth. For a period of 8 to 10 days, the drilling flies initially undergo maturation of bird droppings or bacterial colonies on cherry tree leaves. Just in time for the color change of the fruits from green to yellow, the females are ready for egg laying. In dry weather and ideal temperatures of 20 degrees Celsius, a single female cherry-fly female lays 200 to 400 eggs just below the epidermis of ripening cherries. Since only one egg per cherry is deposited, a few flies are sufficient to destroy the entire crop.
Within 8 to 10 days, the larvae hatch and continue to drill into the flesh. After about three weeks of gluttony near the cherry stone, the maggots and their ripe fruits fall to the ground, where they pupate and overwinter. If the cherries do not fall to the ground, the maggots rappel on thin threads to get into their winter quarters under the earth's surface.
Cover tree pulley in time with fleece
In the first approach of effective control, the flight of the hatched cherry fruit flies onto the tree should be stopped. For this purpose, cover the tree disc in good time with foil or a close-knit cultural protection net. The mesh size must not exceed 0.8 mm to prevent the tiny flies from infecting. The foil or net edges are completely covered with earth to reliably close all loopholes.
As long as there were cherry trees infested with maggots in the previous year, all tree disks are covered with fleece at a distance of 200 meters, because wintering pests could have hid there. Only after the end of the harvest time, the cover can be removed again.
Tip: So that no other generation of cherry fruit flies can pupate in the soil, please regularly turn down fallen cherries and bury the fruits at least 20 cm deep. At the end of the harvest season, all fruit mummies should be removed from the tree and buried as well.
Protective nets prevent ovipositionComplete protection against approaching cherry fruit flies is only guaranteed if, in addition to the ground cover, the crowns are wrapped in protective nets. The insects are naturally sluggish and do not fly more than 100 meters. In case of bad fruit hanging due to damp and cold weather, the pests do not shy away from covering distances of up to 1000 meters. Due to the cumbersome and laborious handling of protective nets, this method of control is primarily suitable for small cherry trees. Numerous home gardeners have begun to cut large cherry trees regularly to the appropriate stature height for the Einnetzung.
Yellow sheets reduce infestation pressureThe color change of the cherries from green to yellow is the signal for the female cherry fruit flies to lay their eggs in the fruit. This process uses yellow boards to capture the pests. Yellow sheets are coated with a special glue and treated with UV-resistant paint. Since chemical additives are not used here, yellow sticky traps are permitted in organic fruit growing and are often used by home gardeners to combat the cherry fruit fly. To apply yellow sheets correctly:
- From the middle of May, hang glue traps in the cherry tree
- Distribute between 3 and 10 copies in the crown
- Until the middle / end of July leave the tablets in the tree
Tip: The clout of yellow sticky traps against cherry fruit flies can be greatly enhanced with a bait.Pour an intense-smelling, organic liquid fertilizer into a small PET bottle without a cap. These hang below a yellow board, whereupon the catching effectiveness doubles.
Early varieties are sparedEarly cherry varieties have long exceeded the yellow-colored stage of maturity at the beginning of oviposition. These cherries are not perceived as a possible breeding ground by the female cherry fruit flies and are mostly spared by maggots. Cheat the unappetizing pests by favoring the following varieties in your garden:
- Kassins Frühherz cherry: Premium variety with brown-red, very juicy cherries; Growth height 3.5 to 5 m (not self-fertile)
- Red maize cherries: high yielding, sweet in the taste, good stone dissolving; Growth height 3.5 to 5 m
- Giorgia: thrilled with space-firm, dark red cherries and sweet aroma; 3.5 to 5 m
- Burlat: large, dark red fruits with aromatic, firm pulp; Growth height 2.5 to 4 m (not self-fertile)
- Earlise: about 3 days before Burlat ripe, but sensitive to space; Growth height 3.5 to 4.5 m (not self-fertile)
Beneficials - valuable help in combating combat
The successful control aims to prevent the pupation of cherry fruit flies and to reduce the number of pupae sustainably. With the following beneficials you receive effective protection from the animal kingdom:
- Chickens enthusiastically pick maggots and dolls from the ground
- Swifts, swallows and other birds hunt for adult cherry fruit flies
- Ground beetles, spiders or parasitic wasps like to eat the larvae
Furthermore, nematodes have proven to be an ecological control agent with high efficiency. Roundworms of the genus Steinernema are supplied by specialist dealers in a clay mineral powder and should be applied in a timely manner. To do this, stir the nematodes in stale water and pour the mixture into a watering can. Distribute the liquid on the tree disc in good time before the start of flight of the cherry fruit flies, the parasitic parasitizes and destroys the pests.
Biocide - last rescue with high infestation pressureIf you are confronted with a hardened cherry fruit fly pack, put an end to the maggot plague with a biological control. The biocide Naturalis is based on the spores of Beauveria bassiana, a naturally occurring fungus. The spores attach themselves to maggots and adult cherry fruit flies alike, spread in the host organism, whereupon it is received within a short time. The remedy is approved for the house and allotment.
The powder is mixed with water according to the instructions of the manufacturer and applied with a conventional sprayer. Important to note is a complete wetting of the entire tree crown including the undersides of the leaves. Best time for the application is the early morning or late evening, because the adult flies in these phases reduce their activity.
The period of control extends from 7 days after the beginning of the flight time to 7 days before the start of the harvest. Experience has shown that 3 to 5 applications are sufficient to harvest maggots-free cherries.