Managing the use of glyphosate-based herbicide in Nova Scotia’s forestry sector

Authors

DOI:

https://doi.org/10.5931/djim.v20i1.12829

Abstract

This report provides an overview of the use of glyphosate-based herbicides in Nova Scotia’s forestry sector, including an analysis of the potential consequences of its use and recommendations for the future of forestry in the province. Potential impacts of glyphosate-
based herbicides on ecosystems, human health, and Indigenous rights are considered. Corporate misconduct by manufacturers of glyphosate-based herbicides is investigated, and the responsibility of governments and regulatory bodies to govern the use of herbicides is examined. In light of the findings of this report, alternative vegetation management methods are considered, and recommendations are provided regarding the future use of glyphosate-based herbicides in Nova Scotia.


Our team recommends phasing out the use of glyphosate-based herbicides in Nova Scotia’s forestry sector. Additional interim recommendations are outlined to provide immediate avenues for action. These recommendations include reversing provincial policies which permit herbicide use on Crown lands, protecting aquatic habitats by amending herbicide setback buffers, establishing meaningful partnerships with Mi’kmaq communities, and adopting a variety of silviculture practices. These recommendations will support Nova Scotia’s forestry sector as it shifts away from the use of glyphosate-based herbicides and towards more sustainable and
environmentally conscious vegetation management methods.

Keywords: glyphosate, herbicide, forestry, Nova Scotia, management, Monsanto, Bayer, genotoxicity

References

Activities Designation Regulations, N.S. Reg. 47/1995. https://novascotia.ca/just/regulations/regs/envactiv.htm

Bacon, M.-H., Vandelac, L., Gagnon, M.-A., & Parent, L. (2023). Poisoning regulation, research, health, and the environment: The glyphosate-based herbicides case in Canada. Toxics, 11(2), 121. https://doi.org/10.3390/toxics11020121

Bayer. (2018, June 7). Bayer closes Monsanto acquisition. Bayer News. https://www.bayer.com/media/en-us/bayer-closes-monsanto-acquisition/

Bayer. (2020). VisionMAX silviculture herbicide commercial solution label. Bayer Cropscience Inc., Calgary, AB. https://www.bayer.com/sites/default/files/2020-10/27736_VisionMAX_Approved_English.pdf

Belchim Canada. (2025). TIMBERLINE Herbicide commercial and restricted solution label. https://www.belchimcanada.com/_files/ugd/bbc081_ecc2b6274b774d8ab20c70a894d8a18e.pdf

Bell, F. W., Pitt, D., Morneault, A., & Pickering, S. (1999). Response of immature trembling aspen to season and height of cut. Northern Jounral of Applied Forestry, 16 (2), 108-114. https://doi.org/10.1093/njaf/16.2.108

Botten, N., Wood, L. J., & Werner, J. R. (2021). Glyphosate remains in forest plant tissues for a decade or more. Forest Ecology and Management, 493, 119259. https://doi.org/10.1016/j.foreco.2021.119259

Brookes, G., Taheripour, F., & Tyner, W. E. (2017). The contribution of glyphosate to agriculture and potential impact of restrictions on use at the global level. GM Crops & Food, 8(4), 216–228. https://doi.org/10.1080/21645698.2017.1390637

Bruggen, A. H. C. van, Finckh, M. R., He, M., Ritsema, C. J., Harkes, P., Knuth, D., & Geissen, V. (2021). Indirect effects of the herbicide glyphosate on plant, animal and human health through its effects on microbial communities. Frontiers in Environmental Science, 9. https://doi.org/10.3389/fenvs.2021.763917

Chapman, K., Fleming, R. L., Thiffault, N., Gouge, D., Kayahara, G. J., Morris, D. M., & F.W, B. (2023). An ecological framework to support the use of herbicide alternatives in boreal and northern temperate forests of Ontario and Quebec –First approximation. https://publications.gc.ca/collections/collection_2023/rncan-nrcan/Fo4-214-1-2023-eng.pdf

Chávez-Ortiz, P., Tapia-Torres, Y., Larsen, J., & García-Oliva, F. (2022). Glyphosate-based herbicides alter soil carbon and phosphorus dynamics and microbial activity. Applied Soil Ecology, 169, 104256. https://doi.org/10.1016/j.apsoil.2021.104256

Chen, C. Y., Hathaway, K. M., & Folt, C. L. (2004). Multiple stress effects of Vision® herbicide, pH, and food on zooplankton and larval amphibian species from forest wetlands. Environmental Toxicology and Chemistry, 23(4), 823–831. https://doi.org/10.1897/03-108

Comeau, P. G., & Fraser, E. C. (2018). Plant community diversity and tree growth following single and repeated glyphosate herbicide applications to a white spruce plantation. Forests, 9(3), 107. https://doi.org/10.3390/f9030107

Davoren, M. J., & Schiestl, R. H. (2018). Glyphosate-based herbicides and cancer risk: A post-IARC decision review of potential mechanisms, policy and avenues of research. Carcinogenesis, 39(10), 1207–1215. https://doi.org/10.1093/carcin/bgy105

Department of Lands and Forestry. (2021, September). High Production Forestry in Nova Scotia Phase 1 Final Report. Nova Scotia. https://novascotia.ca/ecological-forestry/docs/HPF-phase1-report.pdf

Devet, R. (2016, August 18). Glyphosate spraying on Nova Scotia forests continues. Nova Scotia Advocate. https://nsadvocate.org/2016/08/18/glyphosate-in-nova-scotia-an-update/

Department of Natural Resources and Renewables (DNRR). (2023). High Production Forestry in Nova Scotia Phase 2 Guidance for Implementation. https://novascotia.ca/ecological-forestry/docs/HPF-phase2-guidance-for-implementation.pdf

Duffield Timber. (2021, October 21). Hardwood vs. softwood: What are the differences? https://duffieldtimber.com/the-workbench/timber-trends/hardwood-vs-softwood-what-are-the-differences

Duke, S. O. (2018). Interaction of chemical pesticides and their formulation ingredients with microbes associated with plants and plant pests. Journal of Agricultural and Food Chemistry, 66(29), 7553–7561. https://doi.org/10.1021/acs.jafc.8b02316

Ecojustice. (2025, February 20). Federal Court rules Canada’s approval of glyphosate product unreasonable. Ecojustice. https://ecojustice.ca/news/federal-court-rules-canadas-approval-of-glyphosate-product-unreasonable/

Environment and Climate Change (ECC). (n.d.). Pesticide Applications Approvals. Pests and Pesticides. Retrieved April 14, 2025, from https://novascotia.ca/nse/pesticide-spray/

Environment and Climate Change (ECC). (2024, August 15). 2024 Pesticide Spraying Approvals Issued. https://news.novascotia.ca/en/2024/08/15/2024-pesticide-spraying-approvals-issued

Environmental Code of Practice for Pesticides (RSA 2000 cE-12). https://kings-printer.alberta.ca/1266.cfm?page=pesticide2.cfm&leg_type=Codes&isbncln=9780779850730

Environmental Protection Agency (EPA). (2016). Glyphosate Issue Paper: Evaluation of Carcinogenic Potential. https://www.epa.gov/sites/default/files/2016-09/documents/glyphosate_issue_paper_evaluation_of_carcincogenic_potential.pdf

Flint, J. (2025). [New Mad Dog Plus decision] Mad Dog Plus (PCPA Reg. No. 30076) [ECO-ACTIVE.FID42403]. https://safefoodmatters.org/wp-content/uploads/2025/08/August-2025-PMRA-email-Mad-Dog-Plus-decision.pdf

Gandini, E. M. M., Costa, E. S. P., Dos Santos, J. B., Soares, M. A., Barroso, G. M., Corrêa, J. M., Carvalho, A. G., & Zanuncio, J. C. (2020). Compatibility of pesticides and/or fertilizers in tank mixtures. Journal of Cleaner Production, 268, 122152. https://doi.org/10.1016/j.jclepro.2020.122152

Gardner Pinfold Consultants. (2023). Economic Impacts of the Forestry Sector in Nova Scotia. https://static1.squarespace.com/static/650c6b84d6ecf1091eef19a9/t/65df38f7ab404b2c63149b52/1709127930810/GP_Forestry+Update+2023_Final+%281%29.pdf

Gill, J. P. K., Sethi, N., Mohan, A., Datta, S., & Girdhar, M. (2018). Glyphosate toxicity for animals. Environmental Chemistry Letters, 16(2), 401–426. https://doi.org/10.1007/s10311-017-0689-0

Golt, A. R., & Wood, L. J. (2021). Glyphosate-based herbicides alter the reproductive morphology of rosa acicularis (prickly rose). Frontiers in Plant Science, 12. https://doi.org/10.3389/fpls.2021.698202

Gomes, M. P., Smedbol, E., Chalifour, A., Hénault-Ethier, L., Labrecque, M., Lepage, L., Lucotte, M., & Juneau, P. (2014). Alteration of plant physiology by glyphosate and its by-product aminomethylphosphonic acid: An overview. Journal of Experimental Botany, 65(17), 4691–4703. https://doi.org/10.1093/jxb/eru269

Government of Canada. (2023, April 11). Treaties and Agreements. https://www.rcaanc-cirnac.gc.ca/eng/1100100028574/1529354437231

Government of Canada. (2024, February 23). Government of Canada and the Duty to Consult. https://www.rcaanc-cirnac.gc.ca/eng/1331832510888/1609421255810

Grunewald, K., Schmidt, W., Unger, C., & Hanschmann, G. (2001). Behavior of glyphosate and aminomethylphosphonic acid (AMPA) in soils and water of reservoir Radeburg II catchment (Saxony/Germany). Journal of Plant Nutrition and Soil Science, 164(1), 65–70. https://doi.org/10.1002/1522-2624(200102)S164:1<65::AID-JPLN65>3.0.CO;2-G

Guijarro, K. H., Aparicio, V., De Gerónimo, E., Castellote, M., Figuerola, E. L., Costa, J. L., & Erijman, L. (2018). Soil microbial communities and glyphosate decay in soils with different herbicide application history. Science of The Total Environment, 634, 974–982. https://doi.org/10.1016/j.scitotenv.2018.03.393

Hamberg, L., Laine, T., Hantula, J., & Saksa, T. (2021). Long-term effects of biological sprout control of unwanted hardwoods on conifer sites. Forest Ecology and Management, 493, 119288. https://doi.org/10.1016/j.foreco.2021.119288

Health Canada. (2006, January 9). ARCHIVED - Information Note: Pesticide Application Methods and Areas of Use [Transparency - other]. https://www.canada.ca/en/health-canada/services/consumer-product-safety/reports-publications/pesticides-pest-management/fact-sheets-other-resources/pesticide-application-methods-areas-use.html

Health Canada. (2017). Re-evaluation decision: Glyphosate (Nos. RVD2017-01). Health Canada Pest Management Regulatory Agency. https://publications.gc.ca/collections/collection_2017/sc-hc/H113-28/H113-28-2017-1-eng.pdf

Henderson, A., Gervais, J., Luukinen, B., Buhl, K., Stone, D., Strid, A., Cross, A., & Jenkins, J. (2019, March). Glyphosate Technical Fact Sheet. National Pesticide Information Center. https://npic.orst.edu/factsheets/archive/glyphotech.html

Heydens, William. (2003, August 8). RE: K-salt of glyphosate. [Email]. U.S. Right to Know. https://usrtk.org/wp-content/uploads/2017/08/48-Monsanto-discussion-of-3-unexplained-deaths-in-acute-inhalation-tests-of-lab-animals.pdf

Heydens, William. (2012, July 13). RE: Genotox Review [Email]. U.S. Right to Know. https://usrtk.org/wp-content/uploads/bsk-pdf-manager/2020/01/McClellan-Roger-Exhibit-09-Redacted.pdf

Heydens, William. (2015, February 19.) RE: IARC Planning. [Email]. Wisner Baum Law. https://www.wisnerbaum.com/wp-content/uploads/Email-Correspondence-Wherein-William-Heydens-Suggests-Experts-Could-Edit-and-Sign-Their-Names-to-Scientific-Paper.pdf

Integrated Pest Management Regulation (B.C. Reg. 604/2004). https://www.bclaws.gov.bc.ca/civix/document/id/complete/statreg/604_2004#section75

Kier, L. D., & Kirkland, D. J. (2013). Review of genotoxicity studies of glyphosate and glyphosate-based formulations. Critical Reviews in Toxicology, 43(4), 283–315. https://doi.org/10.3109/10408444.2013.770820

Kincaid, E. (2025). Glyphosate safety article retracted eight years after Monsanto ghostwriting revealed in court. Retraction Watch. https://retractionwatch.com/2025/12/04/glyphosate-safety-article-retracted-elsevier-monsanto-ghostwriting/

Kissane, Z., & Shephard, J. M. (2017). The rise of glyphosate and new opportunities for biosentinel early-warning studies. Conservation Biology, 31(6), 1293–1300. 10.1111/cobi.12955

Koskie Minsky. (n.d.). Roundup Class Action. Koskie Minsky. Retrieved April 16, 2025, from https://kmlaw.ca/cases/roundup-class-action/

Krimsky, S., & Gillam, C. (2018). Roundup litigation discovery documents: Implications for public health and journal ethics. Journal of Public Health Policy, 39, 318–326. https://doi.org/10.1057/s41271-018-0134-z

Lahey, W. (2018a). An Independent Review of Forest Practices in Nova Scotia: Executive Summary. https://novascotia.ca/natr/forestry/forest_review/Lahey_FP_Review_Report_ExecSummary.pdf

Lahey, W. (2018b). An Independent Review of Forest Practices in Nova Scotia—Addendum. https://novascotia.ca/natr/forestry/forest_review/FP_Addendum.pdf

Logan, C. (2022, September 22). Anti-glyphosate camps pop up in Nova Scotia forests while spraying is underway. Canada’s National Observer. https://www.nationalobserver.com/2022/09/22/news/anti-glyphosate-camps-pop-nova-scotia-forests-spraying-underway

Loveland Products. (2020, September 24). Mad Dog Plus. https://www.lovelandproducts.ca/sites/default/files/pdf/label-sds/maddogplus_pcp30076_05-2022.pdf

Lozano, V. L., & Pizarro, H. N. (2024). Glyphosate lessons: Is biodegradation of pesticides a harmless process for biodiversity? Environmental Sciences Europe, 36, 55. https://doi.org/10.1186/s12302-024-00884-y

Malkan, S., Klein, K., & Lappé, A. (2022). Merchants of Poison. U.S. Right to Know. https://usrtk.org/wp-content/uploads/2022/12/Merchants_of_Poison_Report_final_120522.pdf

McGrath, T., Pulsifer, M., & Seymour, R. (2021, September). Nova Scotia Silvicultural Guide for the Ecological Matrix. https://novascotia.ca/ecological-forestry/docs/silvicultural-guide.pdf

Meftaul, I. Md., Venkateswarlu, K., Dharmarajan, R., Annamalai, P., Asaduzzaman, M., Parven, A., & Megharaj, M. (2020). Controversies over human health and ecological impacts of glyphosate: Is it to be banned in modern agriculture? Environmental Pollution, 263, 114372. https://doi.org/10.1016/j.envpol.2020.114372

Miller, Jr., Ronald. V. (2025, March). Monsanto Roundup Lawsuit Update. Lawsuit Information Center. Retrieved March 24, 2025 from https://www.lawsuit-information-center.com/roundup-lawsuit.html

Miskin Law. (n.d.). Roundup Class Action. Miskin Law. Retrieved April 16, 2025, from https://www.miskinlaw.ca/class-action/roundup-class-action/#:~:text=Miskin%20Law%20is%20now%20taking,first%20released%20in%20the%201970s.

Noseworthy, J. (2018). New England–Acadian Forest Restoration A Landowner’s Guide to Theory and Practice. Nature Conservancy of Canada. https://www.nswooa.ca/uploads/5/9/6/9/59690537/new_england_-_acadian_forest_restoration.pdf

Nova Scotia. (2024a). Nova Scotia Pesticide Approvals 2024. https://novascotia.ca/nse/pesticide-spray/docs/pesticide-approvals.pdf

Nova Scotia (2024b). Approval No. 2024-3556893-00. https://novascotia.ca/nse/pesticide-spray/docs/2024-3556893.pdf

Nova Scotia Environment and Labour (NSEL). (2007). Media Backgrounder Herbicide Management. https://novascotia.ca/nse/pests/docs/HerbicideBackgrounder.pdf

Nova Scotia Natural Resources and Renewables (NSNRR). (n.d.). Strathlorne Forest Nursery. Retrieved April 14, 2025, from https://novascotia.ca/natr/forestry/strathlorne/

O’Reilly, M., & Shrestha, T. (2013). Highway right of way maintenance: energy use per acre in mowing compared to herbicide application [Conference paper]. 29th Annual International Conference on Soils, Sediments, Water and Energy, Amherest, MA.10.13140/2.1.2594.0160

Pérez, G., Vera, M., & Miranda, L. (2011). Effects of herbicide glyphosate and glyphosate-based formulations on aquatic ecosystems. In Herbicides and Environment (pp. 343–368). https://doi.org/10.5772/12877

Pest Control Products Act, SC 2002, c 28. https://laws-lois.justice.gc.ca/eng/acts/p-9.01/

Pierce, J. S., Roberts, B., Kougias, D. G., Comerford, C. E., Riordan, A. S., Keeton, K. A., Reamer, H. A., Jacobs, N. F. B., & Lotter, J. T. (2020). Pilot study evaluating inhalation and dermal glyphosate exposure resulting from simulated heavy residential consumer application of Roundup®. Inhalation Toxicology, 32(8), 354–367. https://doi.org/10.1080/08958378.2020.1814457

Province of Nova Scotia. (2025). Approval (Nos. 2024-3535010–00). https://novascotia.ca/nse/pesticide-spray/docs/2024-3535010.pdf

Quebec. (2024, September 10). Investing in Québec’s forest products industry. Gouvernement du Québec. https://www.quebec.ca/en/agriculture-environnement-et-ressources-naturelles/forets/entreprises-industrie/invest-forest-products

Riley, C. M., Wiesner, C. J., & Sexsmith, W. A. (1991). Estimating off-target spray deposition on the ground following the aerial application of glyphosate for conifer release in New Brunswick. Journal of Environmental Science and Health, Part B, 26(2), 185–208. https://doi.org/10.1080/03601239109372730

Samsel, A., & Seneff, S. (2015). Glyphosate, pathways to modern diseases IV: Cancer and related pathologies. Journal of Biological Physics and Chemistry, 15(3), 121–159. https://doi.org/10.4024/11SA15R.jbpc.15.03

Safe Food Maters (SFM). (2025, August 19). Mad Dog Case on Glyphosate: PMRA Refuses Action on New Science. Safe Food Matters. https://safefoodmatters.org/2025/08/18/mad-dog-case-health-canada-didnt-weigh-new-science-on-glyphosate-including-forest-studies-and-ramazinni/

Tesar, A. (2018, June 21). Reserves in Nova Scotia. The Canadian Encyclopedia. https://www.thecanadianencyclopedia.ca/en/article/reserves-in-nova-scotia

The Canadian Press. (2025, February 20). The federal government must revisit its approval of a popular weed-killer, court says. CTV News. https://www.ctvnews.ca/canada/article/the-federal-government-must-revisit-its-approval-of-a-popular-weed-killer-court-says/

Thiffault, N. (2021). Forest Vegetation Management: Key Functions, Alternatives to Chemical Herbicides and Challenges. Natural Resources Canada. https://publications.gc.ca/collections/collection_2021/rncan-nrcan/Fo4-169-2021-eng.pdf

Thiffault, N., Hébert, F., Charette, L., & Jobidon, R. (2014). Large spruce seedling responses to the interacting effects of vegetation zone, competing vegetation dominance and year of mechanical release. Forestry: An International Journal of Forest Research, 87(1), 153–164. https://doi.org/10.1093/forestry/cpt048

Thiffault, N., & Roy, V. (2010). Living without herbicides in Québec (Canada): Historical context, current strategy, research and challenges in forest vegetation management. European Journal of Forest Research, 130, 117–133. https://doi.org/10.1007/s10342-010-0373-4

Thompson, D., Chartrand, D., Staznik, B., Leach, J., & Hodgins, P. (2010). Integrating advanced technologies for optimization of aerial herbicide applications. New Forests, 40, 45–66. https://doi.org/10.1007/s11056-009-9181-4

Thompson, D. G., & Pitt, D. G. (2003). A review of Canadian forest vegetation management research and practice. Annals of Forest Science, 60(7), 559–572. https://doi.org/10.1051/forest:2003060

Thompson, D. G., & Pitt, D. G. (2011). Frequently Asked Questions (FAQs) On the Use of Herbicides in Canadian Forestry. Natural Resources Canada. https://publications.gc.ca/collections/collection_2011/rncan-nrcan/Fo123-1-112-eng.pdf

Timms, K. P., & Wood, L. J. (2020). Sub-lethal glyphosate disrupts photosynthetic efficiency and leaf morphology in fruit-producing plants, red raspberry (Rubus idaeus) and highbush cranberry (Viburnum edule). Global Ecology and Conservation, 24, e01319, 1-10. https://doi.org/10.1016/j.gecco.2020.e01319

Tresnakova, N., Stara, A., & Velisek, J. (2021). Effects of glyphosate and its metabolite ampa on aquatic organisms. Applied Sciences, 11(19), 9004. https://www.mdpi.com/2076-3417/11/19/9004

Tush, D., Maksimowicz, M. M., & Meyer, M. T. (2018). Dissipation of polyoxyethylene tallow amine (POEA) and glyphosate in an agricultural field and their co-occurrence on streambed sediments. Science of The Total Environment, 636, 212–219. https://doi.org/10.1016/j.scitotenv.2018.04.246

Varona, M., Henao, G. L., Díaz, S., Lancheros, A., Murcia, Á., Rodríguez, N., & Álvarez, V. H. (2009). Evaluation of the effects of glyphosate and other pesticides on human health in areas targeted by the illicit crop eradication program. Biomédica, 29(3), 456–475. https://doi.org/10.7705/biomedica.v29i3.16

Weber, J. T. (2022). Traditional uses and beneficial effects of various species of berry-producing plants in eastern Canada. Botany, 100(2), 175–182. https://doi.org/10.1139/cjb-2021-0086

Weisenburger, D. D. (2021). A review and update with perspective of evidence that the herbicide glyphosate (roundup) is a cause of non-hodgkin lymphoma. Clinical Lymphoma Myeloma and Leukemia, 21(9), 621–630. https://doi.org/10.1016/j.clml.2021.04.009

Weiss, P., & Burger, L. (2025, March 7). Bayer tells US it could halt Roundup weedkiller sales over legal risks. Reuters. https://www.reuters.com/business/healthcare-pharmaceuticals/bayer-eyes-exit-popular-roundup-amid-us-legal-risks-2025-03-07/

Wiensczyk, A., Swift, K., Morneault, A., Thiffault, N., Szuba, K., & Bell, F. W. (2011). An overview of the efficacy of vegetation management alternatives for conifer regeneration in boreal forests. The Forestry Chronicle, 87(2), 175–200. https://doi.org/10.5558/tfc2011-007

Wisner Baum. (n.d.). Monsanto Roundup Lawsuit. Wisner Baum. Retrieved April 16, 2025, from https://www.wisnerbaum.com/toxic-tort-law/monsanto-roundup-lawsuit/

Wood, L. J. (2019). The presence of glyphosate in forest plants with different life strategies one year after application. Canadian Journal of Forest Research, 49(6), 586–594. https://doi.org/10.1139/cjfr-2018-0331

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2026-06-07

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