Page 18 - Green knowledge 2024

Photo: Erling Fløistad
Broad-nosed weevil – an underrated pest
Pine weevils usually get blamed for insect damages on young spruce seedlings. However,
new findings show that other weevils, such as the broad-nosed weevils, can also cause
significant damages, particularly after prolonged drought.
Planting forests is both expensive and labour-inten-
sive. For forest owners, it is crucial that young seed-
lings have the best possible growing conditions and
are protected from diseases and pests.
Damage to small spruce and pine seedlings is typi-
cally attributed to the pine weevils. However, Tor-
stein Kvamme, senior adviser at NIBIO, draws atten-
tion to the broad-nosed weevil Strophosoma
capitatum - a well-known pest in other European
countries but has remained somewhat under the
radar in Norway.
These beetles feed on a wide variety of plants and
can cause significant damage under the right condi-
tions. While the larvae live on roots, the adult beetles
consume green plant parts, including conifer nee-
dles.
during periods of severe drought and low ground
vegetation.
Broad-nosed weevils feed on conifer needles.
If the roots are strong and the seedlings are not too
small, they can often survive an attack. However,
Kvamme points out that climate change spells bad
news for spruce trees.
“If conditions become so dry that ground vegetation
disappears, it will create more opportunities for
broad-nosed weevil damages,” he warns.
He encourages forest owners to monitor their plant-
ing sites closely. Using larger seedlings with strong
root systems could be beneficial, as this may increase
their chances of survival.
One type of broad-nosed weevil in particular is
responsible for damage to spruce plantations. Newly
established planting sites are especially vulnerable
Purpose: Contact: To inform about the broad-nosed weevil as a pest affecting conifers in Norway.
Senior Adviser (OAP agreement) Torstein Kvamme, Division of Biotechnology and Plant Health.
Email: torstein.kvamme@nibio.no | Phone: +47 900 85 153
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