Viburnum leaf beetle how to get rid
Many gardeners are faced with the consequences of the life of the viburnum leaf beetle, and often come to the decision to remove the bush from their site. However, the pest can be successfully combated, both folk and modern methods. How to keep a beautiful and healthy plant in horsemanship is described below.
Biological Description of the Pest
This beetle is common throughout Europe and belongs to the vast family of leaf beetles, but develops only on viburnum. The insect has the Latin name Galerucella viburni Payk. and was first described by the Swedish naturalist Gustav Paikul in 1798.
Did you know? Viburnum bones have a heart shape and are used in folk medicine as a diaphoretic, as well as for the treatment of diseases of the gastrointestinal tract, kidneys and liver.
What does it look like
External signs of an adult beetle are as follows:
- body length: 5–7 mm;
- form: ovoid;
- mustache: long, about 5 mm;
- color: yellow brown.
The beetle larva can be identified by the following characteristics:
- color: dirty gray or dark brown, becomes greenish yellow with age;
- length: 1.2 mm, then grow to 12 mm.
Life cycle features
The life cycle of an insect is one year, which begins in the spring, approximately in May, when larvae emerge from the overwintered eggs.
Important! The bright red, red-hot, color of the berries of viburnum explains its Russian name, and the Latin Viburnum opulus came from the similarity of the leaves of the culture with maple (opulus — one of its varieties) and the verb viere, meaning "twist, weave."
The development of viburnum leaf beetle occurs as follows:
- Within a few days, the larvae appear on the plant, and in the sun the process occurs 2-3 days earlier than in the shade. They settle on the underside of the leaf and gnaw through the plate, leaving a transparent skeletal base.
- Adult larvae descend to the ground and dig in the upper layer, forming loose cocoons from the ground. After a few days, they become pupae.
- For about 3-4 weeks, the plants remain “free” from larvae and beetles, manage to grow several shoots with young leaves.
- Then young beetles emerge from the pupae, which at first were extremely weak and inactive. They also feed on leaves, gnaw them with oval-shaped holes of different sizes. If the foliage is not enough, beetles can eat young growth and green berries.
- In late summer and early fall, females lay eggs in grooves that gnaw in young shoots. Having laid 18-24 small eggs similar to a brown tubercle, they close the clutch. One female can make 5–28 clutches. In this form, the eggs remain wintering until spring.
How to treat viburnum from leaf beetle than to process
To combat the pest, it is necessary to take into account the period in which the insect is:
Important! Processing fruiting viburnum in autumn can be carried out only 20-30 days before harvest or after removing berries from the plant.
- In the fall and early spring, the plant contains egg masonry.At this time, it is effective to trim infected shoots, as well as their subsequent destruction. The shoots in which the clutches are found already dry in September and are easy to detect by this sign;
- from mid-June to mid-July, larvae can be found on viburnum. You can fight them on small bushes by plucking infected young leaves, with an interval of 1-2 days;
- from mid-July to early August, it is possible to carry out shallow loosening of the soil under the bush, where at that time the leaf beetle pupae are located. It will help to combat them and maintain a stable level of soil moisture, as well as its compaction after loosening;
- if adult beetles are already seen on the plant in August and September, they can be shaken off on a fabric or film spread under a bush.
Chemical treatment of viburnum, if necessary, is carried out twice:
- against larvae - during the period of their appearance on the bush;
- against beetles - at the very beginning of autumn.
Spraying is performed with preparations such as Actellik, Aktara, Bitoksibacillin or Intra-Vir according to the instructions.
Fighting folk remedies
In addition to the above agricultural techniques, you can apply some folk remedies.
The most effective, according to reviews, are the following infusions (per 10 liters of water):
- chamomile, for which 1 kg of dry or 3 kg of green mass is taken;
- from onions, tobacco or hot pepper, which will require 1 kg of fresh, chopped or 500 g of dried, grated fruits;
- from tomato shoots, for which you can take 1 kg of dry or 3 kg of freshly picked tops.
How to protect viburnum from leaf beetle
Effective protective measures for viburnum are:
- timely trimming and destruction of infected plant material;
- feeding and compliance with basic agricultural practices for the care of the plant;
- selection of healthy planting material.
Important! Local forms of plants are most susceptible to pests, and imported varieties demonstrate greater resistance.