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

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

Lethbridge Research and Development Centre

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

Norris, C.E., Gorzelak, M., Arcand, M., Bruhjell, D., Carlyle, C.N., Dyck, M., Ellert, B., Entz, M., Geddes, C.M., Hao, X., Janovicek, K., Larney, F., May, W., Luce, M.St., Van Eerd, L.L., Zhang, T., Beck, R., Cowen, T., Liptzin, D., Morgan, C.L.S. (2023). The story of long-term research sites and soil health in Canadian agriculture. Canadian Journal of Soil Science, [online] 103(1), 164-190. http://dx.doi.org/10.1139/cjss-2021-0174
2023 - View publication details
Tidemann BD, Sharpe S, Geddes CM (2023) Curious and Concerning False Cleavers (Galium spurium) response to Quinclorac. Western Society of Weed Science Annual Meeting, Boise, Idaho. Feb 27 - March 2, 2023. Poster # 36
2023 - View publication details
Sharpe SM, Leeson J, Geddes C, Beckie H, Willenborg C (2022) Survey of Glyphosate- and Dicamba-Resistant Kochia in Saskatchewan. Annual meeting of the Canadian Weed Science Society in Halifax, NS. November 14, 2022.
2022 - View publication details
Geddes, C.M. 2022. FMC Pre-School presents: Let's Talk Kochia with Dr. Charles Geddes. FMC Pre-School AGRC' 103. 2022-02-15. (Oral Presentation).
2022 - View publication details
Geddes, C.M. 2022. Herbicide-resistant weeds. Richardson Pioneer Growing For Success Conference. 2022-02-03. (Oral Presentation).
2022 - View publication details
Geddes, C.M. 2022. Weeds & herbicide resistance: What was observed in 2021? 2022 Alberta Agronomy Update. 2022-01-12. (Oral Presentation).
2022 - View publication details
Geddes, C.M. 2022. Fundamentals of weed control. 2022 Alberta Agronomy Update, Back to Basics Session. 2022-01-05.
2022 - View publication details
Geddes, C.M., Gulden, R.H., Jones, T., Leeson, J.Y., Pittman, M.M., Sharpe, S.M., Shirriff, S.W., Beckie, H.J. (2022). Baseline survey of herbicide resistance in Russian thistle (Salsola tragus L.) finds no resistance in Manitoba. Canadian Journal of Plant Science, [online] 102(1), 246-249. http://dx.doi.org/10.1139/cjps-2020-0260
2022 - View publication details
Geddes, C.M. 2021. Herbicide Resistance – Act now before it’s too late. 2021 Manitoba Agronomists Conference. Dec 14-15, 2021. [Virtual]. (Oral Presentation).
2021 - View publication details
Geddes, C.M. 2021. Prairie herbicide-resistant weed research update. 2021 Pulse Agronomy Workshop. 2021-11-24.
2021 - View publication details
Geddes, C.M. Herbicide resistance in Alberta. Saddle Hills County Webinar Series. 2021-11-17. (Oral Presentation).
2021 - View publication details
Geddes, C.M. 2021. Weed management in Alberta cropping systems. Virtual Guest Lecture. PLSC 499 Cropping Systems Course. University of Alberta, Edmonton, AB, CA. November 16, 2021. Instructor: M. Thilakarathna.
2021 - View publication details
Nair, J., Lima, P.M.T., Abdalla, A.L., Molnar, L.J., Wang, Y., McAllister, T., and Geddes, C.M. 2021. Kochia (Bassia scoparia) harvest date impacts nutrient composition, in vitro degradability, and feed value more than pre-harvest herbicide treatment or herbicide resistance traits. 2021 American Society of Agronomy (ASA) – Crop Science Society of America (CSSA) – Soil Science Society of America (SSSA) International Annual Meeting Nov 07-10, 2021. Salt Lake City, UT. (Poster Presentation).
2021 - View publication details
Tiffen, S., and Geddes, C.M. 2021. White cockle [Silene latifolia Poir.]. Weed Wisdom. October 2021. Farming Smarter Monthly E-newsletter. 23 Views.
2021 - View publication details
Makela, K., et al. (2021). Biovigilance: A Modern Approach to Plant Pest Management (Vision Statement), Agriculture and Agri-Food Canada, Science and Technology Branch: 29 pp.
2021 - View publication details
Geddes, C.M., Tidemann, B.D., and Sharpe, S.M. 2021. AAFC Herbicide resistance research update. Saskatchewan Crop Diagnostic School. 2021-07-28.
2021 - View publication details
Geddes, C.M. 2021. Kochia loves this drought! Weed Wisdom. July 2021. Farming Smarter Monthly E-newsletter.
2021 - View publication details
Geddes, C.M., and Tidemann, B.D. 2021. Wicked weeds of the west and their bioclimatic drivers. Agriculture and Agri-Food Canada, Alberta Science Conversation Seminar Series. 2021-06-23. (Oral presentation).
2021 - View publication details
Oosterhuis, K. Canola School: Managing weeds early in the season. Realagriculture.com. 2021-04-12.
2021 - View publication details
Geddes, C.M. 2021. Kochia biology and control. Virtual Guest Lecture. Weed Science Course. University of Alberta, Edmonton, AB, CA. Mar 24, 2021. Instructor: N. Kav
2021 - View publication details