Plan to Protect Environmental Assets from Lantana - Weeds Australia

Plan to Protect Environmental Assets from Lantana
6.3.2 Measuring the response of high-priority assets to lantana control
As the ultimate aim of lantana control conducted under this Plan is to protect biodiversity—
particularly those species or ecological communities that are high-priority assets —the assets’
response to control must be measured to accurately gauge the efficacy of lantana control
programs. For example, the recruitment levels of native plant species present at the site will
have important implications for the long-term success of any lantana control program. The
number of seedlings of high-priority taxa can indicate their ability to recover/regenerate
following lantana control programs. A lack of seedlings could suggest that additional
restoration techniques, such as revegetation, fire or soil disturbance, may be needed (Turner
and Virtue 2006, Turner et al. 2008b, Turner and Virtue 2009).
Monitoring the response of the environmental assets can be conducted in a similar fashion to
monitoring the response of lantana. The main issue is choosing which assets to monitor and
finding a suitable monitoring technique for those selected. With respect to this Plan, native
biodiversity at risk has been identified (as listed on the website:
www.environment.nsw.gov.au/lantanaplan/biodiversityatrisk.htm) and this Plan will adopt the
monitoring guidelines from the Bitou Bush TAP (Hughes et al. in press). Hence, monitoring for
this component of the P lan will be determined in consultation with stakeholders and based on
the high-priority assets present at each site and the skill level of land managers and workers.
Alternatively, if resources are available, all native species at a site can be monitored (by
presence/absence or cover abundance), which will show the response of the broader
community.
6.3.3 Measuring the response of other weed species to lantana control
The control of one weed species, in this case lantana, can lead to the invasion of a site by
another weed species (see Reid et al. 2008, Turner and Downey 2008 ). Sometimes this
secondary invader can be more difficult to control than the original weed species. Therefore, a
list of 144 weeds likely to invade after lantana control has been developed (see Section 2.8).
There is a need to also monitor these weed species during and after the control of lantana if
they are present at a site. The number of other weed seedlings will indicate the need for other
control programs; thus, monitoring programs should measure the recruitment of lantana as
well as other weed species present.
6.3.4 Monitoring the response of animals to control
Wherever possible, monitoring the impacts of both lantana invasion and lantana control on
fauna should be considered during a lantana control program. In addition to focusing on highpriority
animal species, such monitoring could also focus on generic groups of fauna (such as
birds), depending on the resources available, the skill or knowledge level of the observer, and
the level of understanding required. As outlined in Section 4.5.1, more detailed information on
monitoring techniques for fauna will need to be developed, or sourced from elsewhere.
6.3.5 Additional research
As discussed previously, data on the impact of lantana and its control on fauna and flora are
limited. Such information is necessary to manage and better protect threatened biodiversity.
Data on the impact of herbicides on threatened species is also limited, and most is anecdotal.
Rigorous examination into the affect of herbicides on threatened species needs to be
undertaken. The above areas of research had already commenced during the development of
this Plan, with research students receiving funding to investigate:
the post-germination growth of native seedlings in the presence of lantana, and to
determine if thresholds exist in relation to impacts of lantana on native plant richness
and abundance (University of Wollongong) (see Gooden 2007, Gooden et al. 2009a,
Gooden et al. 2009b)
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