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Forestry - Pesticides in

Herbicides in Forestry

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also see glyphosate 

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. 

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.

filed under Wildlife/ aquatic organisms and forestry