The box tree moth (Cydalima perspectalis) is a nocturnal butterfly native to East Asia. The pests have also been widespread in Germany and neighboring countries since around 2007. As so-called neozoa (i.e. invasive species), they hardly fear any natural enemies in this country, and the animals come from a similar climate and feel very comfortable here.
Box tree moths have to be combated at different times with different measures
Biology and way of life determine the right time
Only those who have been informed about the life cycle of the box tree moth can effectively tackle the pest. Especially if biological insecticides such as Bacillus thuringiensis are to be used, you should know your enemy. The ideal time to use the spray is when the moth is still at the beginning of its development. Since its eggs hibernate inside the box tree, the caterpillars hatch very early in the year: from around the beginning of March, when the temperatures are permanently above around seven to nine degrees Celsius, the big feeding begins. Special box tree moth traps also help you to discover flying moths.
Fight box tree moths - when you should do what
As soon as one gets caught in one of your traps, you must act. Adult female moths lay up to 150 eggs in their short lifespan of around nine days. You have to be quick to stop the offspring from hatching. Between three and five populations arise annually, i. that is, the borer multiplies incredibly quickly. And this is how you fight the animals:
1. Late February / early March:
- Examine the inside of the box trees for white webs, cut them out
- If necessary, dust box trees with algae lime
2. From early March
- remove hatched caterpillars
- Cut back boxwood
- Cover box trees with plant protection nets
3. Late April / early May
- Install pheromone traps for box tree moths
4. From the beginning / middle of May
- Spray biological insecticides (Bacillus thuringiensis / azadirachtin).
- Mechanical control for weak infestation (high-pressure cleaner, (119.90 €) vacuum cleaner, etc.)
tips
If you want to protect your boxwood from infestation with a plant protection net, choose green nets that are as close-meshed as possible - these are less noticeable. The nets can only be removed in autumn, when the temperature is consistently below seven degrees Celsius.