Bushland Weeds Manual - Environmental Weeds Action Network

Chapter 4 Corms, Bulbs and Tubers Case Studies
and the current policy is to allow
indigenous species to recolonise
treated sites unassisted.
One of the major weeds that
invades sites where bulbous weed
control has taken place on the
sandy soils of the Swan Coastal
Plain is Perennial Veldgrass
(Ehrharta calycina). A spray
program using Fusilade ® is
successfully controlling this weed
over much of Shenton Bushland
including the study site.
Stopping the spread
The distribution of Yellow Soldier in
Shenton Bushland is not dependent
on disturbance, with populations
extending into relatively intact
bushland (Figure 1, Chapter 2).
Preventing spread into undisturbed
areas is the primary aim of the
control program.
Yellow Soldier spreads within the
bushland via seed. The populations
are generally quite discrete
suggesting seed is not easily
dispersed over long distances.
Table 1. Costing of Yellow Soldier control over time.
Source: Brown et al. (2002).
Water movement and human
activity play a role in the spread.
Fire reduces competition from the
native vegetation and creates bare
areas where the seed can
germinate.
Fire, however, can also create
opportunities for land managers to
prevent further spread and
establishment. After fire, Yellow
Soldier plants are clearly visible and
the reduced cover of native
vegetation makes the resprouting
flowering bulbs an easy target for
herbicide control.
Understanding the current
distribution of the weed allows any
new infestations to be recognised,
recorded and targeted for control.
Note: In this trial, the metsulfuron methyl
was, where possible, targeted at Yellow
Soldier and not applied as a blanket
treatment over all vegetation. This is not a
difficult or time consuming task but does
require responsible operators with a
reasonable knowledge of the flora. There is
evidence from other studies that some native
species, particularly seedlings, are
susceptible to metsulfuron methyl at 5 g/ha
(Moore 1999).
How the study was used
In the two years since the results of
the study became available to the
Friends of Shenton Bushland, they
have secured funding to implement
control of Yellow Soldier across the
bushland. The map helped provide
information for costing the project
and indicated clear objectives to
funding bodies. The Friends have
since hired an experienced
contractor with knowledge of the
flora who has carried out the work.
With approximately one hectare of
bushland currently invaded the cost
of control is relatively low. In the
first year funding was obtained
through a state government grant
and in the second year the local
government authority agreed to
fund the follow-up work and should
continue to do so until the
populations require only occasional
hand-removal.
YEAR TREATMENT COST/HECTARE AREA COST
2001 Brush-off @ 2.5 - 5 g/hectare + pulse@2 mL/L. $300.00/hectare ~ 1 hectare (from maps) $300.00
2002 Brush-off @ 2.5 - 5 m/hectare + pulse@2 mL/L. $300.00/hectare check 1 hectare $300.00
2003 As above but also consider hand weeding isolated plants. $300.00/hectare check 1 hectare $300.00?
2004 Now only hand weeding isolated plants may be required. check 1 hectare
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