Research

Basic research, which explores invasive species biology and invasion phenomena, is over-represented in peer-reviewed research on invasive species compared to applied or interdisciplinary research. Invasive species managers are typically most interested in applied research, which is directly aimed at solving a management problem, and interdisciplinary research, which combines ecological research with policy or social sciences (Matzek et al. 2014). Research on invasion theory and invasibility (the characteristics of habitat that make it prone to invasion) is generally more of interest to researchers than managers and is also popular in publication (Matzek et al. 2014, Renz et al. 2009).

Research on invasive plants tends to focus on certain species to the exclusion of others. Hulme et al. found that papers addressing perennial grasses and forbs and annual grasses tend to dominate the literature and that woody species may not be adequately represented relative to their impacts and management challenges (2013). A literature review in California found that just three invasive plant species, none of them woody, accounted for 36% of all papers reviewed (Matzek et al. 2014). Funding may also play a role as there is likely to be more funding available for further research on species for which economic losses and ecological harm are well-documented.

In applied research, certain management approaches, including biological control and cultural controls such as prescribed fire, water level adjustment, and soil nutrient manipulation, tend to be over-represented in published literature compared to manager demand. Conversely, research on management with herbicides, off-target impacts, the impact of application timing, and early detection approaches appear to be under-represented compared to manager demand (Matzek et al. 2014). Although N’ Guyen et al. only looked at research related to one species, they found that research related to spread prevention and early detection rapid response (EDRR) strategies was significantly under-represented considering that prevention and EDRR are generally viewed as the most cost-effective approaches to invasive species management (2016). Another noted limitation is that applied research studies rarely provide information about the monetary costs (e.g., equipment and labor) for the practices being used (Matzek et al. 2014), which is a critical consideration for real-world application.

Field work underpinning scientific publications typically occurs in a 1-3 year timeframe and is often done in a single habitat type (Matzek et al. 2014). The duration of research projects is frequently constrained by funding grant timelines and by the typical trajectory of PhD or post-doctoral studies. Conversely, land managers are often working at sites with multiple habitat types over the course of decades.

In professional fields, siloization occurs when people communicate primarily with others in the same job role and do not communicate much with people in different but related roles within the larger area of expertise. In the invasive species field, siloization means that managers speak and work mostly with other managers while researchers speak and work mostly with other researchers.

A survey of California land managers found that the managers’ top sources of information for decision making on invasive plant management were 1) their own trial and error experiences over time, and 2) speaking with other managers. Attending conferences with research-based presentations and consultation of peer reviewed literature ranked poorly by comparison. Thirty-four percent of managers said that they never consult peer reviewed literature (Metzek et al. 2013).

Siloization may be somewhat less intense though still a concern in the Midwest. A survey of Midwestern managers and researchers found that 47% of managers reported working with researchers and 67% of researchers reported working with mangers (Renz et al. 2009). This survey did not ask about manager utilization of published literature compared to other sources of information. The Midwestern survey indicated some important barriers that may contribute to siloization: Adequacy of time and funding and establishing appropriate contacts were listed as the top barriers to collaboration among both groups (Renz et al. 2009).

Access to scientific literature may be an obstacle for some managers. Metzak et al. found that about 40% of journals that frequently publish invasive species research are pay-walled (2014), meaning that managers would need to either be subscribed through their institution, pay a per-use fee, or use a reference library to access those sources. In a survey of managers conducted by the same team, respondents who reported not using peer-reviewed literature indicated that lack of time or access to obtain articles from research libraries was the primary reason for not consulting the literature (Metzak et al. 2013). In the Midwest, 55% of managers indicated that lack of access to published information was a moderate or significant barrier to use (Renz et al. 2009).

• Hulme, P.E., Pyšek, P., Jarošík, V., Pergl, J., Schaffner, U. and Vilà, M. 2013. Bias and error in understanding plant invasion impacts. Trends in Ecology and Evolution, 28: 212-218.
• Matzek, V., Pujalet, M., and Cresci, S. 2014. What managers want from invasive species research versus what they get. Conservation Letters, 8(1): 33-40.
• Matzek, V., Covino, J., Funk, J.L., and Saunders, M. 2013. Closing the knowing–doing gap in invasive plant management: accessibility and interdisciplinarity of scientific research. Conservation Letters, 7(3): 208-215.
• N’ Guyen, A., Hirsch, P.E., Adrian-Kalchhauser, I., and Burkhardt-Holm, P. 2016. Improving invasive species management by integrating priorities and contributions of scientists and decision makers. Ambio, 45(3): 280-289.
• Renz, M., Gibson, K.D., Hillmer, J., Howe, K.M., Waller, D.M., and Cardina, J. 2009. Land manager and researcher perspectives on invasive plant research needs in the Midwestern United States. Invasive Plant Science and Management, 2: 83-91.