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

1994). Only 3 of 186 exotic grasses imported for potential use as pasture species in northern Australia between 1947 and 1985
proved to be solely useful and not weedy, while 17% subsequently became weeds (Lonsdale 1994).
N. neesiana seed would not have been difficult to obtain. It was, for example, included in a widely circulated list of seed
available from the 1948 harvest at Uppsala Botanical Garden, Sweden (Nannfeldt 1949). N. neesiana was imported to Australia
under the Commonwealth Plant Introduction (CPI) program, established in 1930 to introduce exotic forage and pasture plants for
the ‘improvement’ of grasslands (Cook and Dias 2006). Two CPI importations are currently known, in 1945 (CPI accession
numbers 9731) and 1951 (CPI accession number 13476) (Cook and Dias 2006). The US Department of Agriculture ran a similar
introduction program and imported 11 accessions of N. neesiana to the USA between 1945 and 1972 (Cook and Dias 2006). Two
were still listed as available for distribution in 2006 (USDA ARS 2006): PI 237818 from Spain, donated in 1957 and PI 311713
from Chile, donated in 1966. Some of the USDA material may may have been exchanged with Australia (Cook and Dias 2006).
From 1949 to 1952 N. neesiana was also imported to Canada from Argentina, Bolivia, Chile and Uruguay, and grown in
experimental plots at the Plant Research Institute, Ottawa (Bowden and Senn 1962).
The full extent to which CPI Nassella accessions were trialled or released in Australia has not yet been adequately investigated.
The fate of imported forage plant material was “often poorly recorded” (Cook and Dias 2006 p. 610), and the absence of trial
information does not necessarily indicate a failure to grow the species in the field. Cook and Dias (2006) were unable to list any
evidence of N. neesiana testing, but the species was trialled in Western Australia (Rogers et al. 1979), a State where it not known
to be currently established. Testing of the plant was a component of “small sward” “nursery” trials for the Western Australian
perennial grasses evaluation program during the period 1943-1968. The material grown was found to have ‘little promise’ (low
to moderate productivity or survival or low leaf/stem ratios) at CSIRO Glen Lossie Field Station, Kojonup (some time between
1951 and 1968), and ‘some promise’ (fair to moderate production and fair to good survival) at Muresk Agricultural College
(1943-47). Many other identified and two unidentified “Stipa” and Nassella spp. were also evaluated under this State
Government program (Rogers et al. 1979). In nothern Australia, trial plots for testing potential pasture species were “often
simply abandoned after use” leaving the plants free to naturalise and spread (Lonsdale 1994 p. 350). But although other tested
grasses in the Western Australian trials have subsequently established in the Kojonup and Muresk areas, Nassella spp. have not
been found (Sandy Lloyd, Agriculture Western Australia, in litt. 18 February 2008).
Cook and Dias (2006 p. 608) mistakenly claimed that Ratcliffe (1936) discussed the potential use of exotic “Stipa” for arid land
rehabilitation. However Ratcliffe’s study was influential in the establishment of State government soil conservation authorities in
Australia (Cook and Dias 2006), which experimented with a wide range of exotic plants. In Victoria, the Soil Conservation
Service was involved in trial uses of Nassella after 1963 (Cook and Dias 2006), but according to Zallar (1981) these involved
only N. hyalina (CPI No. 25801 from the USA), although another stipoid, Amelichloa brachychaeta, was also trialled.
Detailed genetic comparison of world populations is probably capable of narrowing down the probable origin(s) of Australian
material.
Victoria
McLaren, Stajsic and Iaconis (2004 pp. 64-65) suggested that an exotic stipoid grass ‘introduction epicentre’ in the northern
suburbs of Melbourne was possibly linked to the trotting stables of Edgar Tatlow, east of Darebin Creek in Epping, and the
possible importation of horses and hay from South America. This suggestion was sourced to a personal communication by P.
Haberfield, who linked Nassella leucotricha to the Tatlow property, presumably marked today by suburban Tatlow Drive, east of
Epping Secondary College. Numerous streets to the east including Trotting Place and Derby Drive suggest the probable extent of
the property. Nassella leucotricha, a Mexican and southern USA species, was locally known as Tatlow grass and had, like N.
neesiana, first been recorded in Victoria at Northcote in October 1934 (McLaren et al. 1998, McLaren, Stajsic and Iaconis
2004).
Tatlow, who died at the Epping property, ‘Derby Lodge’ stud, in March 1968 (Anon. 1968), cannot be blamed for the original
introductions of N. neesiana or N. leucotricha to Victoria, because these precede the transfer of his business from Tasmania.
However he may have been responsible for later Nassella introductions. Records indicate that in 1938 he purchased the horse
‘Raider’ in the USA and imported it to his Tasmanian stud, also called ‘Derby Lodge’, at Hagley (Pedigree Online 2007), near
Launceston. Tatlow frequently imported horses, including ‘Globe Derby’, imported to Hagley in 1927, ‘Belle Logan’ from New
Zealand, and ‘Ayr’, bought in Christchurch in 1932. He also regularly visited “America”, where, in 1954, he purchased Stanton
Hall and Volo Chief (Anon. 1968). Tatlow moved to Epping, some time after 1938. “Most of the broodmares at his studs in both
Tasmania and Victoria were purchased in NZ, many from Southland, and he was a regular visitor to America, where he
purchased ... successful sires” (Anon. 1968). N. neesiana might have been imported with horses from New Zealand, where it was
probably present from the late 1920s, although it has never been recorded from Southland or Christchurch (Slay 2002a), and N.
leucotricha might have accompanied animals purchased in the USA, where it is native in Texas and Oklahoma (McLaren, Stajsic
and Iaconis 2004).
An equine connection otherwise appears to be sound speculation. Horses frequently create areas of bare ground in pastures, are
commonly provided with supplementary fodder, and pass a high proportion of consumed seed in their dung. Horses readily carry
weed seeds externally and create ‘windows’ on the ground surface for their germination and establishment, so horse pastures are
commonly much weedier than those grazed by sheep and cattle (Gurr et al. 1996). Presence of grass seeds such as Bromus
diandrus in horse dung and other data (Weaver and Adams 1996) suggest the possibility that horses could well have dispersed N.
neesiana seed to Australia.
There is substantial evidence for the northern suburbs of Melbourne ‘Nassella epicentre’ hypothesis. McLaren et al. (1998)
referred also to a [another?] report by P. Haberfield of N. charruana being present near Cooper Street at Epping from before
1958. The east end of Cooper St is about 900 m south of Tatlow Drive. The first official record of this species in Australia was a
specimen collected on 21 February 1995 at Thomastown by A. Muir (Hansford 2006). Thomastown is about 3.6 km south of
Tatlow Drive, downstream along Darebin Creek. Later in 1995 N. charruana was found on a rural property at Epping in an
infestation believed by the property owner to have been present since the 1950s (Hansford 2006). Mapping of 45 infestations that
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