Principle species colonised.
The Large pine weevil can attack a variety of young conifer and broadleaved tree species.
Identification.
Adult weevils are dark brown with patches of yellow or light brown hairs organised in random rows on the abdomen/wing cases. They are roughly 10 to 13 mm long (not including the extended “snout” or rostrum). The legs are either deep red or black, with a characteristic tooth at the end of the tibiae (lower leg) and on the femora (the leg segment closest to the body).
Type of symptoms.
When feeding damage to the bark of live young trees occurs, especially between April and September, it is usually indicative of the presence of adults. This damage manifests as feeding scars, which are patches of missing bark that can cause seedlings to become malformed or die.
The threat to host.
If the sites are not managed, large pine weevil can seriously harm newly planted, immature forests within the first five years after replenishment.
The bark of living trees and other woody plants is what the adult beetle eats, however it prefers the bark of young trees. A huge population of weevils can destroy thousands of young trees on a recently refilled site, and its feeding damage can kill a young tree if it girdles the stem (trunk).
On a refilled site where they are not protected, the insect can kill 50% of newly planted fir trees on average. Even in situations when measures have been made to protect them with pesticides, in the worst-case scenario, it can destroy them altogether.
Impact / Effect / Significance
The softwood timber industry in the UK faces the greatest threat. The establishment of replacement crops of conifer trees, such as pines, spruces, firs, and hemlocks, planted or regenerated after the preceding crop has been harvested, is especially at risk. The health of the UK’s conifer forests is essential to hundreds of millions of pounds in investment and thousands of jobs in the forestry, nursery, lumber haulage, and timber processing industries. To maintain the damage to manageable levels, forest and woodland managers must be on the lookout for this pest at all times and take prompt, appropriate action.
