Takachiho scale

Systematic position. The Takachiho scale (Parthenolecanium takachihoi) belongs to the order Hemiptera, family Coccidae. It is a sap-sucking insect primarily recognized as a significant pest of woody plants, particularly prevalent in East Asian regions where it can cause localized outbreaks in orchards and ornamental gardens.

Affected crops. The pest shows a strong preference for members of the Rosaceae family. Its hosts include various species of fruit trees such as plum, cherry, peach, and apricot, as well as several ornamental shrubs like hawthorn. Severe infestations can significantly stunt tree growth and reduce the overall health of the planting.

Biology and life cycle. The life cycle consists of egg, nymph (crawler), and adult stages. Females produce convex, hardened scales that protect them while they feed and lay eggs. The insect typically overwinters as second-instar nymphs sheltered within bark crevices. As temperatures rise in spring, they resume feeding, complete development, and prepare for the next generation.

Nature of damage and pest status. The damage is caused by the extraction of plant phloem sap. Beyond the loss of nutrients, these insects excrete large amounts of honeydew, which serves as a substrate for sooty mold fungus. The resulting coating hinders photosynthesis, leading to branch dieback, leaf chlorosis, and a substantial decrease in fruit production and quality.

Protection measures. Effective management requires an integrated pest management (IPM) approach. Dormant oil sprays are highly effective in targeting overwintering nymphs. During the growing season, systemic insecticides should be applied precisely when the nymphs (crawlers) are active and vulnerable. Regular pruning and the removal of heavily infested wood are essential to reduce the population density.