Weeds in southwest Alberta: new research findings

Editor's Note: This guest article comes from a land down under, but the research is about our neck of the woods. Thank you to Dr. Sonia Graham for submitting to OWC's blog!


In mid-2016 ranchers, private companies, government organisations and non-government organisations (NGOs) were interviewed as part of a social research project titled “Collective Weed Management in Canada”.

The aim of the interviews was to learn about the working relationships that influence the management of weeds in southwest Alberta, and particularly the municipal district of Pincher Creek (Figure 1).

This report provides a summary of the preliminary results of the interviews.
For more information about the project please contact: sonia.graham@unsw.edu.au


  • Thirty people participated in phone interviews between April and August 2016.
  • Thirteen ranchers as well as staff of three private companies, six government organisations and five NGOs were interviewed.
  • The interviews involved open-ended questions about interviewees’ experiences with and perceptions of: the most problematic weeds in the region; the key issues surrounding the management of weeds; relationships between ranchers and the other organisations involved in the management of weeds; and the future of weed management.
  • This document presents the preliminary findings of the interviews. No detailed analysis of the data is presented nor conclusions drawn. That will be conducted in the next stage of the project.

The most problematic weeds

Interviewees identified 38 different weeds that they were concerned about (Figure 2).

The seven weeds that were most commonly mentioned (in order of the frequency with which they were mentioned) were: blueweed, leafy spurge, oxeye daisy, Canada thistle, knapweed, orange hawkweed and burdock. All seven of these weeds were mentioned by at least one-third (10) of the interviewees. Blueweed was mentioned by half (15) of the interviewees.

The reasons offered as to why these seven weeds were considered to be particularly problematic were:

  1. BLUEWEED. Spreads rapidly, outcompetes native vegetation, is toxic to livestock and is harder to kill than other weeds. There was particular concern about the spreading of blueweed with floods and gravel extraction and use.
  2. LEAFY SPURGE. Is widespread, affects other plant species, and is difficult to control even with biocontrol.
  3. OXEYE DAISY. Is a prolific seeder, very competitive and has expanded considerably in the last two to three decades.
  4. CANADA THISTLE. Has been abundant for a long time and makes all types of land, including forestry and agriculture, unproductive. It can cause pink eye in cattle. Some people have a higher tolerance for this weed because it has been a problem for so long.
  5. KNAPWEED. Is a growing problem in Alberta; it has been a significant problem in British Columbia and Montana. It is unpalatable to cattle. Some perceive it to be easier to kill than other weeds.
  6. ORANGE HAWKWEED. Is one of the most recent weeds to be identified as problematic because there are large populations of it in British Columbia with considerable potential for it to spread to Alberta.
  7. BURDOCK. Is spread by (wild) animals and is problematic for horses but is easily controlled by spraying. 3
Figure 2. Number of interviewees who identified each weed as being problematic.

Figure 2. Number of interviewees who identified each weed as being problematic.

The most significant weed management issues

There were four significant issues that interviewees believe affect the successful management of weeds. These were:

  • The historical presence of weeds – The previous movement of weeds across the landscape as a result of human activity, or inactivity, as well as changes in climate experienced to date have contributed to the scale of the problem being dealt with today.
  • The movement of weeds across the landscape – There was considerable discussion in many of the interviews about the growing numbers of weeds that are entering south-western Alberta from neighbouring provinces and further abroad. The vectors that were perceived to be particularly problematic were recreational vehicles (mentioned by almost one-third of the interviewees), railways, pipelines, powerlines, (wild) animals, flooding and gravel extraction and use. This meant that there was a perceived need for early detection and rapid response.
  • Prioritising weeds for control – one challenge of controlling weeds at both regional and property scales is prioritising which weeds to control. At a regional scale this can be made challenging by different types of private and public property managers who have different understandings of: the environmental and economic impacts of weeds; what weeds are problematic; and what the best methods of control are.
  • The everyday reality of controlling weeds – Almost two-thirds of the interviewees mentioned resources/funding/labour and awareness raising/information sharing as significant issues that affect weed management. Only three interviewees mentioned both of these issues. This indicates that interviewees either focus on the need for resources, including both funding and labour, or awareness raising and information sharing.
  • Other issues that fell within this theme were the importance of having time to control weeds as well as within-season timing of weed control efforts. There was also some concern expressed about the challenges of getting many different people to engage in weed control.

 The future of weed management

There were approximately equal numbers of interviewees who were positive and negative about the future of weed control in south-western Alberta. This was true when interviewees discussed weed management in general or specifically on private or public land.

• THE POSITIVE PERSPECTIVE. Some interviewees felt positive about what they had achieved on their own properties. This was because they had been able to invest resources into weeds year after year, or had recently been able to invest more resources into weed management. There was also a sense that large numbers of other agricultural property owners as well as the Municipal District of 5 Pincher Creek were also actively controlling weeds and that there is growing awareness about weeds more generally.

• THE NEGATIVE PERSPECTIVE. Some interviewees felt negative about the future of weed management. There was concern that despite their efforts the weed problems are getting worse. Partly this was attributed to the continual introduction of new weeds to the region or because the resources available are insufficient to deal with the scale of the problem.

• THE NEUTRAL PERSPECTIVE. Two interviewees indicated that they are neither positive nor negative about the future of weed management. These interviewees indicated that they cannot see a big improvement in the control of weeds nor do they think it will change much in future. While they acknowledged weeds might be under control, they are not becoming less of a problem.

Interviewees identified a range of opportunities and barriers to effective weed management in the future.


  •  An increased capacity for sharing information, as a result of the internet and other information technologies, was seen to be a key opportunity to improve weed management in future.
  • There was also enthusiasm about alternative weed control options, such as using goats or other grazing strategies, as well as new technologies, such as mapping and drones.
  • There was optimism about the evolution of more cooperative weed management and research in future.


  • Most of the barriers mentioned were consistent with the significant issues mentioned in the everyday reality of controlling weeds, such as funding and raising awareness (see previous section).
  • Other barriers that were occasionally mentioned included: herbicide resistance, jurisdictional complexity and insufficient research about the impacts of particular weeds and the best ways to control them.

Concluding remarks

These preliminary findings reveal that there are a wide range of weeds that are of concern to land managers in south-western Alberta. The weeds that are perceived to be most problematic are those that are widespread, persistent and are difficult to control, those that have considerable agricultural and environmental impacts, as well as those that are only just beginning to be detected.

Concern about the movement of weeds across the landscape was also evident in interviewees responses to about the most significant weed management issues. Other key issues for now and the future involve raising awareness and obtaining sufficient resources. Such concerns are not specific to south-western Alberta, but are also common among land managers in Australia.

There was considerable optimism about the future of weed management, with over onethird of interviewees feeling positive about what they’ve achieved on their own properties, as well as having a sense that more people are aware of the problem and doing things on other properties. While there was some concern expressed about neighbouring land managers not doing weed control, these seemed to be the exception rather than the norm.

Funding: This research was funded by the University of New South Wales School of Social Sciences.


Dr Sonia Graham
School of Social Sciences
University of New South Wales