By Zsofia Szendrei
Asparagus beetles cause the most economic damage during harvest when they feed on spears and lay eggs. However, if large beetle populations are not managed after harvest, they can also cause serious damage to the fern. Both adult beetles and their larvae feed on the fern’s cladophylls tiny leaf-like structures and strip away the green tissue from the stems. This feeding reduces the plant’s ability to photosynthesize to build up energy reserves for the next season’s harvest. The last generation of beetles in the fern will also overwinter in fall, emerging in spring to cause harvest season issues. Good fern season management can reduce the number of beetles overwintering within and around fields.
What can growers do?
Non-chemical controls
To help reduce beetle numbers for the following growing season, mow the fern in late fall and again in early spring. This practice helps by removing or breaking down the stalks that adult beetles use as overwintering shelter, lowering their survival through the winter.
Source : msu.edu