Maple seed weevil

Bradybatus kellneri is a specific species of weevil belonging to the family Curculionidae. It is recognized as a significant pest primarily targeting the seeds of maple trees (genus Acer), which makes it a critical subject for silviculture and nursery management.

The beetle primarily affects maples such as the Norway maple (Acer platanoides). While adults may feed on young buds and leaves during the early season, the primary destructive phase occurs during the reproductive development of the host tree.

The life cycle of the insect is strictly synchronized with the flowering and fruiting phenology of its host. Overwintering adults emerge in early spring. Females bore into the developing fruits (samaras) to deposit eggs. The larva develops internally, consuming the embryonic tissue, which effectively kills the seed.

The damage caused by Bradybatus kellneri is characterized by reduced seed viability and premature drop of infested samaras. Field indicators include tiny circular exit holes found on the fruit shells. High levels of infestation can lead to a near-total loss of the seed crop, impacting natural regeneration in forests.

Effective management strategies focus on both cultural and chemical control. Key practices include the removal and destruction of leaf litter and surface debris where adults overwinter, as well as the application of approved insecticides during the spring emergence phase before oviposition begins. Regular monitoring of adult populations near maple stands remains essential for successful protection.