Literature review: Impact of Chilean needle grass ... - Weeds Australia

USA: once found on ballast dumps in Mobile, Alabama (Hitchcock and Chase 1971, McLaren et al. 1998, McLaren, Stajsic and
Iaconis 2004), first recorded in 1935 (Gardener 1998), but “no recent collections” (Barkworth 1993) and “has not persisted”
(Barkworth 2006), although it is currently mapped as naturalised in Mobile County (USDA NRCS 2006, Zipcode Zoo 2006).
Mexico: (Zipcode Zoo 2006); several records, earliest 1896 (Verloove 2005). Verloove noted the widespread misapplication of
the name Stipa setigera (= Nassella mucronta) to N. neesiana in Europe and apparently considered Mexican material had also
been misidentifed. N. mucronata was recorded as widespread in Mexico by Reyna and Barkworth (1994) and present in Mexico
by Barkworth and Torres (2001), but these authors did not recognise the presence of N. neesiana in that country.
South America: Introduced prior to 1921 to the Juan Fernandez Islands of Chile, where well established (Baeza et al. 2007).
Probably introduced elsewhere in South America, but the native range is difficult to determine.
Australia
Maps: Walsh (1994 - Victoria), Liebert (1996 - Victoria), McLaren et al. (1998 - Australia), Gardener (1998 all known
Australian records, plus dates of important regional distribution points), Thorp and Lynch (2000 - Australia), ARMCANZ et al.
(2001, Australia, with distribution points for each decade from the 1930s), Bruce (2001- mainly natural temperate grassland sites
in the ACT), Mallett and Orchard (2002), Frederick (2002 - North Central Region, Vic.), Ens (2002a - Cumberland Plain,
Sydney), McLaren et al. (2002b – south-eastern Australia, based on a survey of land owners and managers in areas thought
likely to be infested and including absence data), Jim Backholer, DPI Victoria (2006 – Australia, reproduced in Snell et al.
2007and below as Fig. 3). The grid map of Thorp and Lynch (2000) allowed for display of areas of low, medium and high
density but no high density areas were shown; the distribution displayed included only Victoria and a small area of south-eastern
South Australia and was based only on records provided by Primary Industries and Resources South Australia and the Victorian
Department of Natural Resources and Environment. Data consisted of 0.5º cells for South Australia and 0.25º cells for Victoria.
The most recent and most comprehensive national map is that produced by Backholer in September 2006 for the National
Chilean Needle Grass Taskforce (Fig. 3).
Anderson et al. (2002) noted that there were no published estimates of the area of Australia infested. McLaren, Weiss and
Faithfull (2004) noted that there were also no published records of the area infested for the States in which it occurred. By
surveying landholders in areas known to have N. neesiana populations in Victoria, New South Wales and the Australian Capital
Territory, McLaren et al. (2002b) determined that infestations were dispersed over an area of over 4 million ha and that the plant
was still actively dispersing in Victoria.
Distribution in the States and Territories of Australia is summarised below, and more detailed records are provided in the
following section on the history of the plant’s dispersal in Australia. N. neesiana was not recorded from the Australian Alps by
McDougall and Walsh (2007).
Victoria: Northcote - first Australian record 1934 (McLaren, Stajsic and Iaconis. 2004); widespread in the Port Phillip,
Corangamite, Glenelg-Hopkins, North Central, Goulburn and North East Catchment and Land Protection Regions with scattered
records in West Gippsland and Wimmera Regions.
New South Wales: Glen Innes - first NSW record 1944 (McLaren, Stajsic and Iaconis. 2004); Central Coast, Northern
Tablelands including Glen Innes, Guyra (Duncan 1993), Tenterfiled, Emmaville (Gardener 1998), Southern Tablelands (Wheeler
et al. 1990) including Bungendore (Eddy et al. 1998), North West Slopes (Storrie and Lowien 2003), Cenral West Slopes (data
points in map in McLaren et al. (2002b); widespread on roadsides in the Sydney region (bounded approximately by Rylstone,
Singleton, Nowra and Taralga) (Carolin and Tindale 1994). 16 sites on the Cumberland Plain, Sydney region (Ens 2002a), first
recorded in the Cumberland Plains at Mount Annan Botanic Garden in 1989 (Benson and von Richter 2009); within the Sydney
region mainly in Western Sydney (Benson and McDougall 2005); Balranald (Sheehan 2008).
Australian Capital Territory: near Burbong “from where it may spread downstream along the Molonglo” River (Burbidge and
Gray 1970). Found at 82% of sites investigated in the Canberra area in 2000-01(Bruce 2001); extensive additional sites detected in
2002 (Sharp 2002). Currently very widespread and a major component of suburban ‘nature strips’ and lawns (S. Sharp and J.
Connelly pers. comms. 2006, personal observations).
South Australia: first recorded in 1988 (Jessop et al. 2006) at Lucindale (McLaren et al. 1998), considered naturalised (Storrie
and Gardener 1998); South East (Thorp and Lynch 2000); Northern Lofty region (near Bundaleer), Southern Lofty region, South
East (Lucindale) (Jessop et al. 2006). ) Okagparinga Valley by late 2000 (Obst and How 2004). 53 infestations in the Mt. Lofty
Ranges, Fleurieu Peninsula and greater Adelaide regions totalling 14.0 hectares recognised up to December 2003, including
Modbury (moderate to heavy, 0.07 ha), Adelaide Parklands (5 plants removed by hand), Clarendon (one site, 0.02 ha, low
density, grazed pasture) and Wirrina (several sites, 13.77 ha) (Obst and How 2004).
Queensland: southern (Mallet and Orchard 2002, Michael Hansford in Iaconis 2003), in the Shires of Clifton, Warwick and
Cambooya (Phil Maher in Iaconis 2006b).
Tasmania: Hobart area (Mallett and Orchard 2002, Hocking 2005b).
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