Dr. Charles M. Geddes, Ph.D., P.Ag.

Image Charles M. Geddes
Research Scientist - Weed Ecology and Cropping Systems
  • Herbicide-resistant plants
  • Weed ecology, biology and management
  • Integrated weed management
  • Weed seedbank dynamics
  • Crop/weed interference
  • Long-term agroecosystem experiments

Current research and/or projects

16. Principal Investigator. Title "Old plots, new hypotheses: Toward a revitalized AAFC long-term agroecosystem experiment (LTAE) network." AAFC Management Solicited Initiative. 2019-2022.

15. Principal Investigator. Title "Development of an integrated weed management (IWM) package to mitigate and manage glyphosate-resistant weeds in soybean." WGRF, MPSG, CAP Ag Action MB Program. 2019-2024.

14. Principal Investigator. Title "Management of glyphosate-resistant kochia in western Canadian cropping systems." ICA Cluster - CAP, WGRF, MPSG, MWBGA, AAFC. 2018-2023.

13. Principal Investigator. Title "Weed seed-suppressive soils: Managing herbicide-resistant weed populations at the source." AAFC A-base. 2018-2021.

12. Co-Investigator. Title "Beneficial insects in Prairie crops: quantifying the value and vulnerability of biological pest control." AAF, AWC, AB, SWDC. 2019-2022.

11. Co-Investigator. Title "Development of improved protocols for the culture of arbuscular mycorrhizal fungi with high symbiotic potential according to the analyses of soil microbiome." AAFC A-base. 2018-2021.

10. Co-Investigator. Title "Delivery of an innovative winter wheat package to achieve sustainable wheat production in the Canadian Prairies." CNW Cluster - CAP. 2018-2023.

9. Co-Investigator. Title "Glyphosate-resistant kochia/Russian thistle surveys." WGRF. 2018-2023.

8. Co-Investigator. Title "Identifying agronomic and environmental benefits and drawbacks of diverse crops in cereal/canola/pulse crop rotations on the semi-arid Canadian Prairies. DFC Cluster - CAP. 2018-2023.

7. Co-Investigator. Title "Improving the management of sclerotinia stem rot of canola using fungicides and better risk assessment tools. CAR Cluster - CAP. 2018-2023.

6. Co-Investigator. Increasing the suitability of the Holos model for life cycle analysis through production cycle inputs, collaborative/open source development, and the development of representative farm systems. AAFC A-base. 2019-2022.

5. Co-Investigator. Integrating multiple beneficial management practices (BMPs) in an organic cropping system: Soil health, weed and insect interactions. AAFC A-base. 2018-2021.

4. Co-Investigator. Title "Long-term sustainable canola production - All phases rotations. WGRF, ACPC. 2017-2020.

3. Co-Investigator. Title "Manipulating agronomic factors for optimum canola harvest timing, productivity and crop sequencing." CAR Cluster - CAP. 2018-2023.

2. Co-Investigator. Title "Mitigating herbicide resistance - Investigating novel integrated weed maangement systems." WGRF, ACPC, ABC, SWDC. 2016-2021.

1. Co-Investigator. Title "The right balance: Management strategies for plugging organic soil health constraints and moving forward." OS Cluster III - CAP. 2018-2023.


Education and awards

Doctor of Philosophy (Plant Science), University of Manitoba, 2018

Bachelor of Science (Agroecology), University of Manitoba, 2012

Key publications

For a complete list of publications, please visit: AAFC Online

Nair, J., T.K. Turkington, R.E. Blackshaw, C.M. Geddes, N.Z. Lupwayi, S.Xu, J. Yang, H. Yang, and T.A. McAllister. 2019. Impact of field fungal contamination of barley on ensiling properties, nutritional quality and the microbiome of barley silage. Grass and Forage Science 74:231-243.

Geddes, C.M., and R.H. Gulden. 2018. Candidate tools for integrated weed management in soybean at the northern frontier of production. Weed Science 66:662-672.

Johnson, E.N., Z. Wang, C.M. Geddes, K. Coles, B. Hamman, and B.L. Beres. 2018. Pyroxasulfone is effective for management of Bromus spp. in winter wheat (Triticum aestivum) in western Canada. Weed Technology 32:739-748.

Geddes, C.M., and R.H. Gulden. 2017. Early autumn soil disturbance decreases persistence of volunteer summer-annual oilseed rape (Brassica napus). Weed Research 57:182-192.

Geddes, C.M., A. Cavalieri, F. Daayf, and R.H. Gulden. 2015. The allelopathic potential of hairy vetch (Vicia villosa Roth.) mulch. American Journal of Plant Sciences 6(16):2651-2663.


Alberta Institute of Agrologists (member)

American Society of Agronomy (member)

Crop Science Society of America (member)

Canadian Society of Agronomy (member)

Canadian Weed Science Society (member)

Weed Science Society of America (member)