Apple flatheaded borer

The apple flatheaded borer (Agrilus mali) is a wood-boring beetle belonging to the Buprestidae family within the order Coleoptera. This insect is a significant pest of orchard crops, primarily targeting the vascular tissues of stems and branches, which can lead to the decline of productive trees.

The primary hosts for this species are apple trees, but it also infests pears, hawthorns, and various other plants within the Rosaceae family. The insect is particularly attracted to trees that are stressed, injured, or have thinning canopies, although mass outbreaks can affect healthy specimens as well.

Its biological cycle is typically univoltine, meaning it completes one generation per year. The larvae overwinter in chambers excavated within the wood or under the bark. In late spring or early summer, they pupate, and adult beetles emerge, feeding on foliage before mating and laying eggs on the bark surface.

The damage is caused by larvae constructing irregular, serpentine galleries beneath the bark. These tunnels disrupt the flow of nutrients and water, causing the bark to crack and swell. Over time, these girdling tunnels can cause branches to wither, leaves to yellow, and eventually result in the death of the tree.

Integrated pest management strategies for the apple flatheaded borer include:

• Regular orchard inspections to identify and remove infested wood and dead branches.
• Maintaining tree vigor through proper irrigation and balanced fertilization to increase resistance.
• Applying white latex paint or whitewash to trunks to prevent sunscald, which attracts egg-laying females.
• Using targeted insecticide sprays during the adult flight period to reduce the population.
• Encouraging natural predators, such as woodpeckers and parasitic wasps, in the orchard environment.