Government of British Columbia Home
Forests, Lands & Natural Resource Operations
Invasive Plant Program

Evaluation and Research

The use of biocontrol agents requires a commitment to evaluate the agents once they have been released to the landscape for control of their target plant. Evaluation can address many topics, including:
  • Monitoring release sites to determine whether the agent has established;
  • Monitoring the area to determine if the agent is dispersing;
  • Investigating whether the targeted plant is being affected at the release site;
  • Investigating possible impact of the agent on non-target plants;
  • Investigating interaction among biocontrol agents and cumulative effects of multiple agents targeting one plant species; and
  • Evaluation of changes in plant and animal communities coinciding with biological control of invasive plants.

Evaluation can take many forms, ranging from cursory observations to intensive research trials. The Ministry of Forests, Lands and Natural Resource Operations is committed to evaluate the biocontrol agents released in B.C. and the Biocontrol Development Program (BDP) is involved in a variety of evaluation efforts. Several of the topics listed above are addressed in-house while others are addressed through partnerships with similar-focussed agencies. The BDP is open to expanding these partnerships to ensure proper evaluations of biological control releases are conducted in BC.

Some examples of evaluation conducted by the BDP include biocontrol agent establishment and dispersal monitoring, which results in data entered into the Invasive Alien Plant Program (IAPP) Application. Data collected via transects or with Biocontrol Success Images to document the effect of biocontrol agents on the target plant at specific release sites is also entered into IAPP. The following table summarizes a few of the more in-depth studies the Biocontrol Development Program has engaged in.

Table 1. Biocontrol Development Program Evaluation Research

Evaluation Study Partnering Agency Field Completion Date Publication Status
BC knapweed case study MFLNRO Range Branch and Forrex Ongoing In development
BC diffuse knapweed decline MFLNRO Range and Research Branches 2009 Newman,R.F, S. Turner, B.M. Wallace, and S. Cesselli. The decline of diffuse knapweed in British Columbia.
Population threshold study of Rhinocyllus conicus on marsh plume thistle None Ongoing In development
Impact of Rhinocyllus conicus on marsh plume thistle seeds AAFC 2010 Unpublished data
Effectiveness monitoring for Mecinus janthinus control of Dalmatian toadflax None Ongoing In development
Effectiveness monitoring for Mecinus janthinus control of Dalmatian toadflax AAFC Ongoing Publications in development
Establishment monitoring and overwintering success of Mecinus janthinus for control of Dalmatian toadflax. AAFC 2002 De Clerck-Floate R. and V. Miller. 2002. Overwintering mortality of and host attack by the stem-boring weevil, Mecinus janthinus Germar, on Dalmatian toadflax (Linaria dalmatica (L.) Mill.) in western Canada.
Landscape level impact of Mecinus janthinus on Dalmatian toadflax in southern BC. AAFC and Forest Practices Branch 2007 Publication in review: Van Hezewijk, B.H., R.S. Bourchier and R.A. De Clerck-Floate. 2010. Regional-scale impact of the weed biocontrol agent Mecinus janthinus on Dalmatian toadflax (Linaria dalmatica).
Effectiveness monitoring for Mogulones cruciger control of hound's-tongue None Ongoing In development
Impacts of Mogulones cruciger on hound's-tongue infestation None 2002 Unpublished data
Establishment, dispersal and effectiveness monitoring of Mogulones cruciger, biocontrol agent for hound's-tongue.

Includes development of optimum strategies for agent release for increased rate of effectiveness.
AAFC Long term monitoring ongoing Two publications:
De Clerck-Floate, R.A., B. Wikeem, and R.S. Bourchier. 2005. Early establishment and dispersal of the weevil, Mogulones cruciger (Coleoptera: Curculionidae) for biological control of houndstongue (Cynoglossum officinale) in British Columbia, Canada.

De Clerck-Floate, R. and B. Wikeem. 2009. Influence of release size on establishment and impact of a root weevil for the biocontrol of houndstongue (Cynoglossum officinale).
Monitoring for impact on non-target Boraginaceae by Mogulones cruciger, biocontrol agent for hound's-tongue. AAFC with U of Idaho, and recently with UBC Okanagan Long term monitoring ongoing Two publications:
De Clerck-Floate, R. and M. Schwarzländer. 2002. Host specificity of Mogulones cruciger (Coleoptera: Curculionidae), a biocontrol agent for houndstongue (Cynoglossum officinale), with emphasis on testing of native North American Boraginaceae.

Andreas, J.E., M. Schwarzländer, and R.A. De Clerck-Floate. 2008. The occurrence and potential relevance of post-release, nontarget attack by Mogulones cruciger, a biocontrol agent for (Cynoglossum officinale) in Canada.
Monitoring the impact of Mogulones cruciger on hound's-tongue population traits/genetics. AAFC, and Université catholique de Louvain, Belgium Began 2009 and ongoing In development
Monitoring the effect of fertilization on weed biocontrol agent population growth and effectiveness, using the hound's-tongue biocontrol system as a model. AAFC Ongoing One publication to date, and more in development:
Van Hezewijk, B.H., R.A. De Clerck-Floate and J.R. Moyer. 2008. Effect of nitrogen on the preference and performance of a biological control agent for an invasive plant.
Effectiveness monitoring trial for Longitarsus quadriguttatus control of hound's-tongue None Ongoing In development
Effectiveness monitoring trial for Rhinusa antirrhini control of Dalmatian toadflax None Ongoing In development
Efficacy and interaction trial for knapweed bioagents - Cyphocleonus achates, Larinus minutus, Larinus obtusus, Agapeta zoegana and Urophora affinus (and secondarily Chaetorellia acrolophi and Terellia virens) AAFC Ongoing One publication to date:
Crowe, M.L. and R.S. Bourchier. 2006 Interspecific interactions between the gall-fly Urophora affinis Frfld. (Diptera: Tephritidae) and the weevil Larinus minutus Gyll. (Coleoptera: Curculionidae), two biological control agents released against spotted knapweed, Centaurea stove L. ssp. micranthos.
Evaluation of potential spread, impacts and suitability of invasive knotweeds for biological control AAFC Ongoing Bourchier R.S. and B.H. Van Hezewijk 2010. Distribution and potential spread of Japanese knotweed in Canada relative to climatic thresholds.
Sphenoptera jugoslavica dispersal sampling in MFLNRO's Southern Interior Region MFR RSI 1994 Unpublished data

Where available, MFLNRO sponsored publications on biocontrol evaluation and research and references pertinent to biocontrol are housed in the Invasive Plant Research Compendium (IPRC). The IPRC also houses references for multiple topics on invasive plant management.  For additional information regarding on-going research in the province please view the Invasive Plant Council of BC's British Columbia Invasive Research Database.

"Healthy, functioning BC ecosystems, free of the impacts of invasive plants."