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Monitoring Protocols: Impact
of Control Method
Purpose
The aim of this protocol is to provide community
groups who are engaged in bridal creeper control work a means
by which to monitor and demonstrate the outcomes of their
projects.
The protocol involves recording the vegetation
types along transect lines. This will give the percentage
cover of different vegetation types found in the study plot.
By taking repeated measurements over time you
can see if bridal creeper is declining, and if native plants
are subsequently increasing. Monitoring should be done during
September each year so that results will remain comparable
through time.
The protocol has been designed specifically
with bridal creeper in mind, however the technique is simple
enough that it may be applied to the monitoring of other weed
control work.
Equipment required
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A tape measure
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Clipboard, worksheet
(PDF 39KB) and a soft lead pencil
for recording data
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Steel posts and pegs for permanently marking the transect(s)
and photo points
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Camera
The Protocol (step by step)
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1. Site selection
For monitoring purposes choose one or several bushland
sites that have dense bridal creeper infestations, few
other major weeds, and an understorey of various native
species (which may well be sparse due to the bridal creeper
invasion).
Estimate the overall size of the weed infestation at your
control site. Use either m2 or hectares, depending on
the scale of the infestation.
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Establishment of transects
Run at least one transect line through the infested area
that includes remnant native vegetation.
If your site is quite variable in the amount of bridal
creeper coverage and/or the type of remnant vegetation,
it is possible to increase the accuracy of the data collected
by setting up more than one transect across different
areas of the site and repeating the exercise (this is
not essential).
Transect length may be scaled to suit the size of the
infestation. For example, if the infestation covers a
hectare or more, a transect length of 50m would be suitable,
conversely if the infestation is 20x20m (400m2), then
a transect of no more than 20m in length is possible.
If the bridal creeper or other vegetation is impenetrable
along the transect, walk around the obstacle and estimate
the distance covered, record it and then recommence the
transect.
Set the transect tape at approximately one metre above
the ground. Be sure to permanently mark the start and
the end of the transect to ensure that the same location
is monitored each time. This can be done with steel fence
posts or wooden stakes (if termites are absent!). Paint
the top of the post with brightly coloured paint to make
the post more visible when revisiting the transect.
It's a good idea to use a secondary method of marking
the transect start and finish points in case the posts
are accidentally damaged, vandalised or stolen. For example,
start the transect at an immovable object (tree or large
rock) and mark it with a paint spot. If you have access
to a metal detector, bury small steel plates beside the
posts. These can be relocated using the metal detector.
We also recommend that you draw a mud map of your site
that includes the location and direction of your transect
(or take photos, see below 'setting up a photo point').
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Vegetation types to be monitored
The measurements to be taken relate directly to the amount
and type of foliage that occurs in the metre between the
tape and the ground. For simplicity the vegetation that
is encountered is broken down into groups such as:
Bridal creeper does grow higher than one metre, usually
in columns, you can record the height to which it grows
and also the species or vegetation type it is growing
on in the Notes section of the data sheet. You could split
the plant groups into natives and exotics if you want.
If time and your knowledge permits you may be able to
identify plants to genus and species level. This depends
very much on how your group wants to document/demonstrate
long-term progress.
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Taking your vegetation measurements
To avoid unnecessary trampling of the vegetation, choose
an access path along the transect tape that will be used
each year. Only the person calling the measurements should
access the tape, with the scribe remaining remote, again
to limit trampling.
Once in position at the 'zero' mark look vertically down
over the tape to the ground, or vegetation below, and
measure the distance that the various vegetation types
occupy between the 0 and 1m mark (with 10cm as the minimum
interval).
For example (see attached example)
50cm bridal creeper, 20cm grasses and herbs, 30 cm shrubs,
20 cm tree (for trees measure the amount of trunk that
intercepts the transect not the canopy cover). Note that
this adds to more than 100 cm; this means that there has
been an overlap of vegetation types with, say, bridal
creeper covering 20 cm of shrubs etc. Continue doing this
for each metre of tape until the end of the transect is
reached.
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Monitoring for the biocontrol agents
Please record if and when either of the biocontrol agents
were released at your site1. For each metre of the transect
where bridal creeper is present, please rank the presence
of the rust and/or the leafhopper.
The ranking system is as follows:
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0=none present
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1=just detectable
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2= medium level damage
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3=severe damage: L=leafhopper, R=rust, e.g., 0L3R
means that the leaf hopper damage was not seen, but
the rust was causing the leaves to yellow.
Even if agents haven't been released/redistributed at
your site they may have spread naturally form a site nearby.
Don't spend any more than 30 seconds or so looking for
the agents in any given metre of the transect.
Each year you should also record any control measures
taken on bridal creeper at the site (e.g. herbicide spraying,
hand weeding etc). Give a brief summary (e.g. date, control
method, rates) that you can refer back to in future years
to help explain why (or why not) the bridal creeper has
declined.
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Interpreting the data
Once the data collection is complete you can then average
the length recorded for each group of vegetation (see
attached example). A simple chart of the length of
the transect covered with each vegetation type can then
be produced (see example). Through time the average amount
(length along the transect) of bridal creeper encountered
should decrease, while at the same time the amount of
desirable vegetation increases. This will not necessarily
happen however, as sometimes one weed is replaced by another
unless there is sufficient seed of desirable species in
the soil to fill the space or revegetation work has been
successfully implemented. Either way this monitoring protocol
will provide the tool to capture this change.
If your monitoring work indicates that other weed species
are invading the area it is recommended that further action
be taken to avoid the replacement of bridal creeper by
other weeds.
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What happens with the information then?
You can use the information accumulated over years to
demonstrate to funding bodies and stakeholders that your
control method has been effective over time. We would
be most interested in having access to your data collected
at sites where you have released biological control agents
for bridal creeper in order to demonstrate the effectiveness
of the agents.
Please post or fax the information to:
Louise Morin
CSIRO Entomology
GPO Box 1700 Canberra ACT 2601
Fax: 02 6246 4362
E-mail: firstname.lastname@csiro.au
What if I am already using another monitoring technique?
Some groups may have already established other ways of
estimating bridal creeper dominance (e.g. recording %
cover in quadrats). If you are comfortable that your technique
could quantify long-term declines in bridal creeper and
recovery of native vegetation then there's no need to
change. However, your data is still valuable to us.
Setting up a photo point
Setting up one or more photo points to capture an image
of your site and transect(s) is a simple method of recording
gross change in vegetation at the site. The photos may
also be used as a reference for finding your transect(s)
should the marker post go missing. Like setting up the
starting point for a transect, the photo point needs to
be permanently marked. When taking your year one photo(s)
it may also be a good idea to record the zoom settings
used on the camera so that the field size of photos can
remain constant through time.
This protocol was prepared by the National Bridal Creeper
Steering Committee, June 2002.
Any question? Contact us
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