Recognize box tree moth: this is what eggs and caterpillars look like

The voracious larvae of a box tree moth can "defoliate" and kill any box tree in record time. The earlier the pests are discovered, the greater the chance of saving the Buchs after all. This is how you recognize the annoying box tree moth.

butterfly

The box tree moth, scientifically Cydalima perspectalis, can be described as a newcomer to the garden. The small butterfly only immigrated from Asia at the beginning of this millennium. His presence will not be of a temporary nature, because he finds ideal living conditions in this country. The butterfly itself does not damage the box tree directly, but rather its larvae. Nevertheless, the alarm bells should ring for every boxwood owner when small butterflies fly around the evergreen shrub in spring or summer. Because wherever the box tree moth shows up, it will soon lay eggs. How to recognize the box tree moth:

• Wingspan is 4 to 4.5 cm
• outspread wings point diagonally downwards, are rounded
• The wing color is silky white
• Fore and hind wings have a thick brown-black border
• rarely white-beige, brown or almost black specimens
• The color of the abdomen is matched to the wings
• black facet eyes
• long, thin antennae

Tip: You can get a special pheromone trap in stores that you can use to attract male book tree borers. This is not an effective control method, but a reliable way to spot the box tree moth and take action in good time.

Eggs

In our latitudes, the box tree moth usually produces two new generations per year. The first egg-laying takes place around April, another follows in July. In southern Germany, where the climate is generally warmer, a third or even fourth egg can be laid.

• each butterfly lays up to 150 pieces
• they are lenticular, pale yellow and only a few millimeters in size
• The storage location is usually a not yet infested box tree
• On the underside of the outer leaves, 20 eggs are close together
• shortly before hatching, small black dots become visible

Caterpillars

After hatching, the larvae are small and yellowish. But it changes quickly. You can recognize adult boxwood moth caterpillars by the following features:

• Length of up to 5 cm
• yellow-green to dark green basic color
• black and white vertical stripes
• black dots are arranged along it
• brown-black head capsule
• white bristles

Keep an eye out for them

The caterpillars of the boxwood moth are large and conspicuous, and yet the infestation is usually discovered too late. This is due to the fact that the hatched larvae migrate into the opaque interior of the box tree and can eat their way out from there unnoticed. When they have reached the outside of the crown, the infestation can be described as advanced. But even then, they are not immediately noticeable, as they hardly stand out from the background due to their pattern. It is therefore important to take a close look at the slightest suspicion or even as a preventative measure. A look inside the canopy should not be missing. These signs indicate caterpillar infestation:

• Leaves and shoots have been eaten away
• white webs are visible in the foliage
• tiny crumbs of excrement on fallen leaves
• Leaf spots (yellow or brown)
• bare (bare) branches

Combat

Discovered eggs are removed from the tree with a courageous pruning and disposed of in a sealed bag as residual waste. Small amounts of pupated larvae can be collected by hand, with large amounts you have to wait until they hatch before controlling them. The caterpillars must be removed or removed from the boxwood as quickly as possible. be killed. Which measure can help most effectively must be decided on a case-by-case basis. The following is possible:

• pick up by hand
• Rinse off the branches with a high-pressure cleaner
• Blow away with a leaf blower
• Spray several times with a preparation made from neem oil
• insert the bacterium Bacillus thuringiensis
• Sprinkle with algae lime
• use chemical spray (only as a last resort)
• natural enemies to settle

A box tree that obviously cannot be saved should be cleared and disposed of as soon as possible. So that the box tree moth cannot spread any further.

Tip: If you blow or flush caterpillars out of the boxwood, you should definitely spread out a large tarpaulin beforehand and fasten it with stones. This makes it easier for you to collect and dispose of all copies after the procedure is complete.

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