Abstract:
Native to Australasia, Eucalyptus (sensu
lato) is one of the most planted genera of trees in the
world. However, the sustainability of Eucalyptus
species as plantation trees in non-native areas is
increasingly threatened by the introduction and spread
of Eucalyptus-feeding insects from Australia. We
examine patterns and potential trends with respect to
the global spread of Eucalyptus-feeding insects.
Likely pathways of introduction and drivers of the
rapid distribution of these insects, as well as management
options are considered. The rate of introductions
is shown to have increased nearly fivefold since the
1980s. As a result, the number of non-native pests of
eucalypts outside of Australia has doubled in less than
three decades. Furthermore, the rate of secondary spread among continents has also increased. Surprisingly,
we found no association between area planted
and the number of pests or new introductions. Only a
small number of countries have been the points of first
detection outside the native range; these countries
have acted as bridgeheads to other regions. Quarantine
regulations aimed at reducing the spread of invasive
organisms appear to be ineffective at a global scale,
and pathways allowing these invasions to occur are
poorly understood or unknown. An expanded suite of
management options are needed to provide resilience
against the rapid accrual and homogenization of
eucalypt pests, thereby ensuring the sustainability of
eucalypt forestry worldwide.
