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Some invasive weeds causing the most concern in Australia are also in Canada

Editor’s Note: Kim Nielsen, an ag fieldman for the County of Clearwater in west central Alberta, is part way through a six-month work experience visit in Victoria, Australia. He is writing regular reports for Grainews on his experiences during his stay.

The last month has flown by at lightening speed and I am now well into my Australian six months weed and pest management program, on loan from Clearwater County Agricultural Services, Rocky Mountain House, Alberta.

I work out of the Hamilton office of the Victorian State Department of Primary Industries, Farm Services Victoria, Landscape Protection portfolio. Coming from my local government organizational level in Alberta to a state level here in Australia was obviously a significant adjustment, but they are eager to hear how agricultural programs are run at a municipal level and conversely I am pleased to participate in their programs also.

The Department of Primary Industries is one of 10 Victorian government departments and with a very strong regional focus they employ more than 2,500 staff at 80 locations across the state. DPI provides advice and support to both the Minister of Agriculture and the Minister of Energy and Resources (agriculture, fisheries, earth resources, and energy and forest industries) and provides services to all Victorians by encouraging the sustainable development of primary industries. The DPI office in Hamilton has a small research station and houses staff from another state department, Sustainability and Environment (water shed resources, climate change, fires, parks and other public land, forests, biodiversity and ecosystem conservation). It is an interesting mix of people, expertise and job descriptions.

Global warming is a popular, and at times divisive, topic here as it is in Canada. The evidence of a warmer and drier climate is easily felt when hearing the news of a third consecutive year of no irrigation in a large portion of the Murray Darling watershed. The impact on farming catastrophic to an area that once was the largest rice producing area in the world. Recently, driving by the now-grassed covered lake in nearby Ballarat, I learned that the 1956 Olympics’ rowing competitions were in fact held there. My surprise over the divisiveness is the fact that despite such obvious signs of climate change there are still a few opinions that it is not human-caused but merely a natural phenomenon.

The picture is from some fascinating work done here at the station under the supervision of Beef Research Scientist John Graham on Nitrous Oxide emissions from different cropping and pastures management scenarios. One way of bringing to light some scientific evidence that agriculture’s impact in many respects fades in comparison to that of other industries.

On the weed and pest front the early detection and rapid response to new and emerging weeds and pest animals is also being adjusted due to global warming and although the Australian climate is distinctly different from the Alberta scenario, they have good reasons to and do take their invasive alien species very seriously.

I have had some involvement with an investigation into a purposely introduced ornamental grass ultimately identified as Mexican Feather Grass (Nasella tenuissima), a state prohibited weed in all states of Australia. Approximately 11,500 plants were sold across Victoria in garden centres since the discovery in May of 2008. This tussock-type grass is extremely drought hardy and imported to fill the demand in “arid gardens,” low maintenance natural garden systems and a trendy fashion in a drought impacted area where watering is an absolute frowned upon practice, unless it is captured rain water from buildings. The high seed production and the ability to spread across much of the Australian landscape has calculated a consequential estimated national economic and environmental impact of Mexican Feather Grass totaling several hundred million dollars annually if the distribution of the 11,500 plants were ignored. DPI took the investigation extremely serious and used DNA technology to remove any shadow of a doubt that the plants sold were indeed that of Mexican Feather Grass.

The seed is thought to have originated from South Africa where many of the other introduced invasives have come from. About 70 per cent of all new invasive plants to Australia are introduced intentionally for ornamental purposes. The Victorian Risk Assessment Tool is a valued asset in prioritizing the list of plants to be on the look-out for and I look forward to comparing this tool to the one recently developed in Alberta.

I have had a chance to work on other weed species as well. The parasitic weed dodder is classified as Restricted Weeds in Alberta and more precisely (as there are some native dodders as well) the Golden Dodder (cuscata campestris) is a regionally prohibited weed in Victoria and thrives in alfalfa and white clover seed fields where they end up as a seed impurity. Giant Knotweed (Polygonum sachalinense), which was actually found in Edmonton last year has shown up in some of the trendy “arid” gardens as well and is another state prohibited weed. In early January I had a chance to visit the Victorian “alps” for some surveying for Orange Hawkweed, which I am a bit familiar with from a couple of small infestations back home in Clearwater County. Orange (Hieracium aurantiacum) and yellow hawkweed or king devil hawkweed (Hieracium pratense) are state prohibited weeds in Victoria and the devastating experience from New Zealand indicates that both hawkweed species could seriously impact much of Australia, especially some of the fragile landscapes such as the “alps.” Anyone traveling to British Columbia through the Sicamous area in late June will attest to both of these plants’ ability to create massive monocultures along roadsides and rangeland. Alberta needs to take this emerging weed threat serious as well.

On a more personal topic I celebrated Christmas on a sheep farm in sunny, 28C weather, having a fabulous lunch in the shade of a gum tree. Really not Christmas to me but I enjoyed the Aussie hospitality including a friendly cricket match afterwards on the lawn.

Harvest is in full swing, a bit strange as we have just entered summer and despite the drought the wheat, barley, bean and canola crops have done relatively well. The annual crops are in reality seeded in the fall but not winter crops as such. They germinate well this time of year as soil moisture improves with winter approaching and the main growth happens late winter and early spring to come to maturity early summer. Slight frosts may impact crop development on a rare occasion but judging by the crops they are pretty comparable to a good crop in Alberta.

The swathed canola crop among the gum trees with a wool shed in the background is from the Casterton area of Victoria and the barley crop being harvested is just inside the state of South Australia near Gladstone, one of the main wheat growing areas of Australia, where harvest is actually completed. Mixed cropping and sheep is a common enterprise using the sheep as a clean-up after harvest.

The Hamilton area is best know for the Grampian mountain range that is part of the Great Divide that runs along the east coast of Australia and bends west through Victoria separating the higher rainfall along the coast and the much drier area in the inside of the range. This picture on the left is taken just prior to landing at the Hamilton airport on a recent return flight from Melbourne and the other is just outside of the little town called Dunkeld 30 km east of Hamilton.

Kim J. Nielsen, Pest Management Officer/ Clearwater County Agricultural Fieldman, Hamilton, Victoria, Australia can be reached at [email protected]au

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