The Content Of The Article:
- Buchsbaumzünsler: appearance and way of life
- Prevention: Caution when buying plants
- How to recognize an infestation
- Fight boxwood growler
The boxwood tree (Glyphodes perspectalis) is one of the most dreaded pests among hobby gardeners, as it has fallen victim to numerous box trees in recent years. So it is not surprising that gardeners try everywhere to protect their lovingly cherished book hedges and balls from him. Anyone who wants to prevent an infestation with the Buchsbaumzünsler or effectively fight him, but must know the lifestyle of the pest. The boxwood borer is native to East Asia (China, Japan, Korea) and was probably introduced to Central Europe with plant imports. In 2007, it was first discovered on the southern Upper Rhine and since then it has spread mainly along the Rhine to the north. He has now immigrated to the Netherlands, Switzerland, Austria, France and Great Britain.
Buchsbaumzünsler: appearance and way of life
The about eight-millimeter-long, young caterpillars of Buchbuszünslers be up to the pupation about five inches long and have a green body with light-dark back stripes and black head. The delta-shaped butterflies are spread out with wings about 40 millimeters wide and about 25 millimeters long. They have bright wings with a characteristic brown border, but there is also a brown shape with white dots.
An overview of the life cycle of the boxwood conifer: The last generation of caterpillars of the year overwinters in boxwood and pupates in spring. From the dolls hatch the butterflies, which deposit new eggs on the box trees within a few days. From this the next generation of caterpillars slips. Every year, two, in very warm regions occasionally three generations occur
The moth itself lives only a few days and is usually not found on the book, but sits on other plants. Only he lays his eggs on the boxwood. The boxwood caterpillars overwinter in webs usually in the interior of cut box trees and begin to eat depending on the weather from mid-March. They go through to pupation several larval stages and live as butterflies barely ten days, in which they then lay their eggs again. The adult moths are therefore not as mobile because of their short lifetime, as is commonly assumed. In Germany, in favorable weather conditions, two to three generations of boxwood growers per year can occur, which is why the pest has increased rapidly within a few years. It can be assumed that about every two to three months a new generation of boxwood breeders hatches.
Prevention: Caution when buying plants
The caterpillar of the boxwood conifer eats on the leaves and young shoots of the plants
Especially through the plant trade, the boxwood grows strong. Examine new boxwoods in the garden center thoroughly for infestation before you buy them. Above all, the weaves and little kisses are treacherous. The caterpillars themselves usually live inside the cut box trees and are harder to spot due to their green camouflage color. In addition, hang some yellow boards in the trees near your box trees. Although these do not significantly reduce the number of butterflies, they do provide information about whether the boxwood conifer can even be found in your garden and when the next generation of caterpillars can be expected.
How to recognize an infestation
Boxwood growers are limited in Central Europe on boxwood species and their varieties. In addition, the insects in their East Asian homeland damage Euonymus and Ilex species. The pests begin to eat inside the plants and are often discovered only when it is almost too late. During its development a caterpillar eats about 45 leaves. After the leaves, the caterpillar caterpillars also gnaw the green bark of the shoots down to the wood, which is why the overlying shoots completely dry up and die off. Unlike the boxwood dying or the boxwood wilt, the eroded leaf ribs remain clearly visible. The infested plants are also covered with webs and dried in places due to the bark damage. Also kotkrümel on the leaf remains can be seen. The caterpillars can damage a boxwood until complete dying.
Fight boxwood growler
As the boxwood borer is an immigrant from Asia, the native fauna is slow to adapt to the insect. In the early years, observations were repeatedly reported that birds immediately choked away the eaten caterpillars. It was thought that this was due to the poisonous plant defenses of the boxwood, which accumulated in the body of the cultured caterpillars.Meanwhile, the boxwood's larvae seem to have arrived in the domestic food chain. Especially sparrows sit in the regions where the Zünsler occurs for some time, during the breeding season to dozens on the Buchseinfassungen and peck out the caterpillars.
In order to prevent an explosive propagation of the boxwood conifer in your garden, you should already fight the first generation of caterpillars in spring. The young larvae are particularly difficult to get along, because they eat inside the boxwood crowns and are protected by webs. For individual plants, you should carefully collect the caterpillars with tweezers - this is tedious, but effective in the long run. But beware: The caterpillars are astonishingly nimble and pull themselves with shock deep inside the box tree crowns. It is even more effective if you "blow through" well-ingrown borders, hedges or bookballs with a high-pressure cleaner or a strong leaf blower. Spread a foil under the plant on the other side so that you can quickly collect the fallen caterpillars.