Greater Necydalis

Systematic position. The Greater Necydalis (Necydalis major) belongs to the order Coleoptera and the family Cerambycidae, commonly known as longhorn beetles. This species is easily distinguished from other longhorns due to its shortened elytra and morphology, which mimics certain species of Hymenoptera, particularly wasps.

Affected crops. This beetle is primarily a secondary pest that attacks weakened or dying deciduous trees. Common host species include various willows (Salix spp.), alder (Alnus spp.), birch (Betula spp.), and occasionally lime or aspen. It is particularly relevant in forest management and the maintenance of shelterbelts.

Biology and life cycle. The life cycle of Necydalis major typically spans two to three years. Adults emerge during the summer months, usually between June and August. After mating, the females deposit their eggs in bark fissures or wounds on the trunks of suitable host trees. Upon hatching, the larvae bore through the bark and begin feeding on the wood.

Nature of damage and harmfulness. Larval activity is the most destructive phase. The larvae create extensive, winding tunnels deep into the heartwood, filling them with frass. This structural damage disrupts the tree's vascular system, leads to wood decay, and significantly reduces the timber quality. In severe cases, the infested trees become susceptible to windthrow and secondary diseases.

Control measures. Management of this beetle focuses on silvicultural practices rather than direct chemical intervention. Key strategies include:

• sanitary logging and removal of infested or severely weakened trees;
• maintaining overall forest hygiene to prevent the buildup of pest populations;
• avoiding mechanical damage to the bark of healthy trees during thinning;
• removing logging residues that could serve as breeding grounds before the emergence period.