|
Abstract:
The results of surveys conducted
in Australia over a five-year period to determine the
distribution of Lantana camara
(lantana) and its introduced biological control agents are
reviewed and discussed. The relative merits and drawbacks of
each species are summarized for the benefit of other countries
wishing to consider biological control programmes against
lantana. Lantana is found in coastal and sub-coastal areas from
far-north Queensland to southern New South Wales (NSW). Small
populations of the weed have been reported around Darwin in the
Northern Territory (NT) and Perth in Western Australia (WA). For
the purpose of this review, lantana is classified into five
varietal groups, based on flower colour. The pink flowering
group is the most common and widespread. It is the only variety
found in southern NSW and in high altitude subtropical areas.
The pink-edged red flowering varietal group is the next most
common, being found from central NSW to far-north Queensland.
The three remaining varietal groups, red, white and orange, are
less common and limited in their distribution. Of the 30
biological control agents that have been introduced into
Australia, 16 have established. The most widespread and damaging
agents are Octotoma scabripennis , Uroplata
girardi , and Teleonemia scrupulosa.
Leptobyrsa decora
is very damaging to lantana seasonally but has a very limited
distribution, being found at only a few sites in high altitude
tropical regions. Two agents, Plagiohammus
spinipennis and Teleonemia harleyi
previously reported as established, were not found in the
surveys. Despite the establishment of 16 agents, lantana is not
under adequate control in Australia. Climate is probably the
major factor that prevents populations of insects from being
maintained at consistently high enough levels to control the
weed.
|
