- Fighting the Book Tree Fighters Now
This year, there's an unusually high number of box tree moth caterpillars feasting on the leaves of boxwoods. The Lower Saxony Chamber of Agriculture advises taking action against these voracious pests now. The caterpillars feed exclusively on boxwood and can cause severe damage. The box tree moth is an invasive species from China.
Pests in April and August should be controlled
"Now is the right time to combat the caterpillars," explains Thomas Brand from the Plant Protection Office of the Chamber of Agriculture. In Northern Germany, the rule of thumb is that pests should be controlled in the months with an 'A', i.e., April or August. Garden owners can collect the caterpillars by hand or prune the boxwoods heavily, as Brand further reported. Affected trees can also be carefully rinsed with a high-pressure cleaner.
Another option, according to the Chamber of Agriculture, is to use approved insecticides that are safe for bees. There are several products that contain a pathogen that only affects caterpillars and is harmless to other insects, mammals, and humans. Other active substances are also effective in controlling the box tree moth. Pheromone traps can only detect the pest and monitor its flight phases. They cannot be used to control the caterpillars.
The pest was introduced around 2006 from China and has since spread throughout Germany and Europe. It has also been observed in Lower Saxony since 2008. Since summer 2018, there have been reports of increasing infestation throughout the state, the Chamber of Agriculture reported.
There are two generations of the pest per year: In spring, the caterpillars feed until around mid-May, after which they pupate. The moth then flies around from early June and lays eggs. The following generation of caterpillars feeds from late July to September on the leaves of the boxwood.
"If you're looking for alternative methods to control the box tree moth, other effective substances can be used besides the pathogen-based ones."
"Despite being an invasive species originally from China, the box tree moth has become a significant issue for garden owners across other regions beyond just Lower Saxony."
