• Learn to Manage Pests Naturally
  • Learn to Keep Insects Out of your Crops
  • Link to SK Organic Resources
  • Grow a Lush Garden Organically
  • SNAP Tour of Organic Vegetable Garden
  • Driving Near Recently Sprayed Fields Exposes People to Pesticides
  • LIving Near Fields Increases Pesticide Exposure
  • Learn About Colony Collapse Disorder and How to Protect Bees
  • Weeds Can Be Managed Without Chemical Pesticides
  • Learn To Manage Weeds Without Chemical Pesticides

Forestry and urban trees - Pesticides in

Herbicides in Forestry

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also see glyphosate,  glyphosate 22,4-Dtriclopyr

a comment from Dennis Loxton on Stop the spray Ontario web site re alternative to glyphosate spraying:    "Just for the record, Sheep Vegetation Management works. Sheep grazing on competing vegetation on reforested clearcuts has proven that Sheep can reduce vegetation competition, enhance wildlife habitat and populations, create high quality food (organic lamb and mutton) and create youth and indigenous employment . Canada already has excellent Sheep, herding dogs, livestock guardian dogs and everything else that you need to create a vibrant, sustainable Sheep Vegetation Management industry. The experiments have already been done and you don't have to invent anything. Also Sheep dairy products are an extra very lucrative bonus as dairy sheep experiments have proven that they can excell at vegetation management on plantations. BC had 50,000 domestic sheep grazing plantations per year recently, until the entire industry was replaced by Roundup spraying because it's cheaper. Moose, and all wildlife and bird populations are crashing out since the BC Roundup spraying program replaced the Sheep Vegetation Management industry in BC."

Digging deep into herbicide impact on forest ecosystems (UNBC Stories, 12 February 2024)          Ecosystem Science and Management Associate Professor Dr. Lisa Wood has garnered an Alliance Society grant ... to lead a five-year project aimed at better understanding the extent of the impact of glyphosate-based herbicides on forest systems.       While consistently finding glyphosate residues in forest plants in past studies, Wood and her collaborators have also documented a reduction in forest foods for wildlife, changes in the chemistry of residual foods present after treatment and they’ve noted how environmental conditions such as temperature and photoperiod impact residue breakdown. Building on that body of work, this new project will delve into if, and how, changes to forest vegetation influence the health of wildlife at different levels in the food chain.     “We’re focusing on how GBH influences gut bacteria and hormones in organisms in the ‘wild’ forest food web, which is a new direction as previous studies of this type have been conducted in more controlled settings.”

Interview about New Brunswick online spray maps for forestry from Caroline Lebbedarcy  (April 2023)    I was interviewed yesterday in my capacity as Chair of SSNB by CHMAfm radio about our two online spray maps which were created a couple of years ago by our amazing computer whizz Gino Doucet. These maps use GNB released data and the maps update automatically every year.   One map lists all forest spray licenses for the current year on public and private forest land.  (new licenses publishe end of July every year)     The historical spray map shows all herbicide (glyphosate mixtures) spraying that has occurred on public land only (GNB only rekeases public land data, which is what our campaign targets).   If you have any questions about our campaign or SSNB merchandise please contact me or Vice Chair Donald Bowser or our other three board members Bruce Dryer, Kimberly Copp and Joël MacIntosh. Note: The maps referenced in this report can be viewed here and here.

Giving Up Glyphosate      The forestry industry’s prized pesticide may be harming people and nature. Is it time to stop spraying? (by Moira Donovan, Maisonneuve, 26 January 2022)     History of glyphosate spraying if forestry, environmental and health effects and the politics. Also  the trial methods that could reduce herbicide use at several points along the process. Ontario and New Brunswick stories.  SNAP Comment: I would like to address the following quote: 'Because mammals and vertebrates don’t have the cellular pathway affected by glyphosate, some scientists and industry players have said that this makes the chemical relatively safe for people.' Whie mammals and people don't have this cellular pathway, the bacteria living within us do and are affected. 

Canfor ‘pest management’ consultation triggers stakeholders’ concerns about glyphosate herbicide  (BC story)   Canfor served notice to forest stakeholders on its five-year ‘pest management plan’ for harvested forest blocks around the Prince George region, but wouldn’t reveal which specific tracts of Crown land are being considered for glyphosate herbicide      (Fran Yanor - Local Journalism Initiative Reporter (The Rocky Mountain Goat)Nov 13, 2020)   '"Forestry management stipulates replanted forests must be 95 per cent conifer. Timber companies are responsible for replanted trees until they reach the ‘free-to-grow’ stage, when they can survive on their own. To speed growth of new conifers, glyphosate solutions are sprayed from planes across massive cut blocks to wipe out deciduous competition.   “It's not based on (ecological) science,” said Steidle. “It's based on the science of agriculture, an agricultural mindset to maximize yields.”    Mike Morris, Liberal MLA for Prince George-Mackenzie, has lived, hunted, fished and trapped in the Prince George Timber Supply Area (TSA) for upwards of 50 years. During that time, he’s seen dramatic effects from logging and spraying.    Forests in the northern interior naturally have a range of deciduous trees and plants, said Morris. “Glyphosate kills that and virtually eliminates all wildlife populations within the area being: sprayed,” said Morris. “It's pretty tragic.”'   SNAP Comment: Glyphosate mostly indirectly eliminates wildlife populations by eliminating their food sources.

Outcry grows as B.C. government agency plans widespread South Coast herbicide spray     The five-year Pest Management Plan, which covers Squamish to Hope, targets native hard woods and Indigenous medicines and food in efforts to increase lumber output. (by Charlie Carey, North Shore News, 24 march 2022)   'The proposed management plan would come into effect on April 1, 2022, and cover the Chilliwack and Sea to Sky Natural Resources District, including the traditional unceded territories of the Stó:lÅ�, St’át’imc, Nlaka'pamux, xÊ·mÉ™θkÊ·É™yÌ“É™m (Musqueam), Sḵwx̱wú7mesh (Squamish), and Tsleil-Waututh First Nations. The proposed plan is for five years, ending in 2027.    While the notice was printed in the local newspaper in Hope, along with the draft proposal available online, it does not include a map of specified locations where herbicides such as glyphosatetriclopyr (Garlon, Release) and 2,4-D (Formula 40) will be used.    The management plan highlights cottonwood, red alder, salmonberry, red elderberry, devil’s club, thimbleberry, salal, fireweed, huckleberry and blueberry as plants which will be targeted by the proposal. All of which, Rose said, Indigenous people have used as medicines and food for thousands of years.“Our rush to get rid of these, so called, competing species is making our forests more vulnerable to wildfire,”'  SNAP Comment: and tht is how you turn a forest into a plantation...

New Brunswick   Legislative committee calls for more glyphosate restrictions, Greens want full ban   Committee recommends greater spray setbacks, asks N.B. Power to stop using herbicides  (Hadeel Ibrahim, , Nov 03, 2021)  Try as I may, I have been unable to get a link to the original report.

10. THAT setbacks for aerial spraying be increased from 500 metres to 1 kilometre from dwellings.

11. THAT the government require a spraying setback of 100 metres from protected natural areas.
12. THAT the government require a minimum 100-metre aerial spraying setback from water and wetlands and/or require spray plans that may vary depending on the landscape and the hydrological characteristics of the land.
13. THAT the government ban spraying of pesticides in protected watersheds as designated under the Clean Water Act.
14. THAT the Minister of Natural Resources and Energy Development request of NB Power that it immediately begin phasing out spraying of pesticides under transmission lines.

Rod Cumberland presentation on glyphosate to N B Standing Committee examining glyphosate use in forests. (June 24, 2021)   Effects of glyphosate on deer population. Rod Cumberland power point presentation on glyphosate June 24, 2021 

Dr. Matt Bett's presentation to N B Standing Committee examining glyphosate use in forests (Professor of Forestry, Oregon State University, 24 June 2021) i hour video presentation. This covers effects of all herbicide used in Oregon, including glyphosate. Biodiversity decreased in plots sprayed once (light spraying)  twice (industrial standard) or 3 times (experimental). Wildlife loss is likely due habitat loss due to herbicide use. More flowers in 3 sprays plots are all invasive species. Although tree growth is 18-20% higher in treated plots, the red spruce germinates very well under canopy and just has to be released by cutting stems besides it. Economic discounting analysis indicates that it likely doesn't 'pay'; to spray. 

Forestry Use of Glyphosate Reduces Fertility of Perennial Flowers and May Reduce Pollination     (Beyond Pesticides, June 22, 2021) 'Glyphosate herbicide use in forested areas persists in the environment for years and can prompt morphological changes in perennial flowers that reduce their fertility and may make them less attractive to pollinators.' 

Let’s talk about herbicide residues in forest communities: what are they doing?  (Dr. Lisa Wood, UNBC - November 13 2020) 1 hour and 16 minutes video presentation. Several charts indicating that  glyphosate and its breakdown products AMPA persist much longer in the "real world" scenario,.When plants such as raspberries and Blueberries are not kiilled outright by glyphosate, they accumulate glyphosate and AMPA intheir tissues and fruits. The first year after spraying, over 70% of samples contained glyphosate and AMPA.. It took 6 years for new raspberry samples contained no herbicide. 

Comments on the Weyerhauser Pasquia-Porcupine 2005 Vegetation Management Demonstration Project Proposal  By Paule Hjertaas; On behalf of Saskatchewan Network for Alternatives to Pesticides (SNAP) (June 14, 2005)  Addresses forest certification and the use of glyphosate in forestry.

Insecticides in Forestry

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Stop the Spray Canada Facebood group _ members only

Stop the Spray Alberta Facebood group _ members only

Stop the Spray BC Facebood group _ members only

Stop Spraying in New Brunswick  Facebood group _ members only

Stop Spraying and Clear-Cutting Nova Scotia (SSACCNS) Facebood group _ members only

Stop the Spray Ontario Facebood group _ members only  They have a petition to sign “Ontario Legislative Assembly: Stop the use of non-essential chemical herbicides in Ontario's public forests ...”. 

From what I gather, Quebec and Saskatchewan are not currently allowing forestry companies leasing provincial Crown land to spray herbicides on the forest.

Other uses of pesticides in Canadian forests

  • In addition to forest companies, many provincial department of highways spray road edges to maintain visibility, railroads spray rail beds for weeds, and power companies spray under power lines. If you become aware of other uses, let SNAP know. 
  • Tree seedlings planted by tree planters also generally seem to be treated, likely with fungicide or insecticides as many tree planters reported to me. I needmore details about this use. 
  • At lest Saskatchewan sprays when needed for insects such as Spruce Budworm and Tent Caterpillars. Btk is an acceptable natural insecticide for organic agriculture and is effective for both. It has generally replaced much more toxic insecticides such as DDT and fenitrothion. Each province would have different rules about this. 

Urban Trees

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also see wildlife section overview

Pesticide Spraying of Urban Trees Found to Disrupt Natural Biological Management of Landscapes  (Beyond Pesticides, November 16, 2022) Putting up with moderate pest levels can attract and maintain predators and parasitoids that provide important biological control services throughout the landscape, according to research recently published in Environmental Entomology.  In general, shrubs underneath scale infested trees contain significantly more pest predators than those underneath uninfested trees. This difference built over the course of sampling time, with three day samples showing less difference than nine day samples.   These findings underscore the importance of patience and timing within the natural pest management approach.   “Treating a tree with pesticides could kill off natural enemies that would otherwise help manage nearby pests. In other words, treating a tree with pesticides could alleviate pest problems within the tree but could result in pest outbreaks in shrubs beneath the tree as natural enemies are killed off.”   SNAP COMMENT: Makes sense. Unsure how it translates to urban plantings with no shrubs. Does that mean that planting trees spaced in rows by themselves makes them more susceptible to pests?

filed under forestry/urban trees and wildlife section overview

also see  Wildlife/ aquatic organisms,mammals glyphosate

Not my area of expertise so I am deferring to groups who work on the issue. I have been told that all provinces except Quebec allow herbicides in forestry. It was my understanding that SK did not use herbicides in forestry before or since I wrote:  "Comments on the Weyerhauser Pasquia-Porcupine 2005 Vegetation Management Demonstration Project Proposal". This proposal to use glyphosate in forestry was defeated. It can be found in publications 

Historically, chemical pesticides started being used after World War II. Nobody worried about their toxicity, it was the age of miracles and the future through chemistry. As a result, the fashion became to use pesticides everywhere including in forests and natural areas.as well as agriculture and municipalities. US forests and pastures were widely sprayed with chemicals including Agent Orange. We know Agent Orange was used on military bases in Canada as well. DDT was also widely used, even in Point Pelee National Park. see Forestry/insecticides in forestry.

Canadian groups working towards stopping the use of herbicides in forestry and links   see above/ Canada   including Stop the Spray Canada Facebook group

Insect problems

In addition to spraying herbicides, mostly glyphosate,.spruce and fir forests used to be sprayed with chemical insecticide all over when there were spruce budworm infestations. When I was in university in the early 1970s, Bacillus thuringensis (Bt), a disease bacterium that sickens the larvae, was starting to replace the much more toxic carbamate, organochlorine and organophosphate insecticides. I believe Bt is now common practice in Canada. Many urban areas took longer to update their spray programsfor urban forests to Bt for cankerworms and other caterpillars, and insecticidal soap for many other insects.

Pesticides used on Seedlings

Another pesticide issue in forestry, from what tree planters have told me, is that all or most of the seedlings planted are treated with pesticides (which ones still unknown at this point, as no one remembered the labels, just the warnings). 

Chemical control in forest pest management  (Stephen B. Holmes and Chris J.K. MacQuarrie, Cambridge University Press:  25 January 2016)   A Canadian history.from Roman and Chinese times to modern. In Canada it starts with DDT in Algonquin Park, Ontario, in 1944-45 and goes throuhg a slough of products including some that were never registered.like Mexacarbate used in Quebec and Ontario (1972-75) to pyrethrins and fenitrothion (until 1998). Then tebufenozide, an insect moulting hormone analogue, temporarily registerd in 1996 for moths and butterflies, like Spruce Budworm. The neonicotinoid imidacloprid is also used in forestry. For control pine bark beetle, the arsenic based herbicide MSMA has also been used on selective trees after bringing the beetles in with a pheromone attractant. Environmental effects of the various insecticides are also mentioned. The article also discusses botanical based insecticides like azadirachtin and spinosyns. The article also discussesaerial application.

Ecosystem Health: Pesticide Use from Forest Management Practices Threatens Essential West Coast Marine Organisms    (Beyond Pesticides, March 11, 2021) A Portland State University (PSU) study finds that pesticides from the forestry industry threaten clams, mussels, oysters (bivalves) along the Oregon state coast. Bivalves are excellent indicator species, signaling environmental contamination through their sedimentary, filter-feeding diet. However, continuous pesticide inputs—from various forestry management regimes—into watersheds along Oregon’s coastal zone endanger these species in downstream rivers and estuaries (river mouths).... The study results detect 12 different chemical compounds (two herbicides, three fungicides, and seven insecticides) in both water and bivalve samples—five of which are current-use pesticides in forest management. Although pesticide concentration and type vary by season, organism, and watershed location, 38 percent of bivalve samples harbor pesticide concentrations high enough to accumulate in tissuesIndaziflam (a current-use herbicide in Oregon forestry) is present in seven percent of bivalve samples. Furthermore, water samples find current-use herbicides hexazinone and atrazine, and banned pesticides like DDT/DDE contribute to aquatic contamination downstream. The study uncovers that most contamination occurs along the Central Oregon Coast in the Siuslaw and Smith watersheds       Additionally, coastal and offshore aquaculture (farming of aquatic organisms) presents a new, looming threat to marine health. Namely, the use of antibiotics and pesticides on local marine ecosystems (e.g., insecticides to control sea lice in farmed salmon) results in coastal habitat loss and genetic and health risks to wild marine populations.   SNAP Comment: As of 23 March 2021, 7 Indaziflam products are registered in Canada, most for orchards and one for non residential/non-crop areas which includes railroads and utilities but not specifically forestry. 5 Hexazinone products with 3 used for alfalfa and blueberries, and 2 for woodland management and Christmas tree plantations, and 12 Atrazine labels which seem to be for use mostly in corn and agriculture. I suspect that extensive water testing in Canada would indicate the presence of many pesticides that likely could accumulate in bivalves and other aquatic organisms. If these particular products were found, the source would likely be agricultural and not forestry. 

Rod Cumberland - Presentation on the effects of glyphosate on deer (YouTube video, 45 minutes)  A New Brusnwick deer biologist explains how he researched the problem of the tumbling New Brunswick deer population and what he found. Softwood tree plantations sprayed with RoundUp to eliminate any other growth are the culprit. No food left for deer or most other species. Indirect effect but massive. Very interesting. the kind of thing one suspects, but to find someone who investigated it is great. A new piece in the puzzle of how we destroy the earth that sustains us.

Forest Management Plans Online  (Ontario Natural Resources)

filed under Wildlife/ aquatic organisms and forestry