Herbicides are shown to decrease biodiversity and harm forests, Jim Hilton explains this week. (Black Press File Photo)

Herbicides are shown to decrease biodiversity and harm forests, Jim Hilton explains this week. (Black Press File Photo)

COLUMNS: Herbicide use in forests reduces biodiversity

Jim Hilton talks about the past and current impacts herbicides on forests

Using herbicides in agriculture as well as forestry has often been controversial.

In a recent B.C. government press release, the spraying of forests to control deciduous plants that interfere with conifers was reduced from 16,000 hectares to 10,000.

Concerns over the impacts on wildlife was the main reason cited particularly relative to ongoing declines in moose populations. The complete elimination of herbicides may be a problem for some forest companies who are required to meet a minimum stocking of conifers as prescribed by government regulations.

Some silviculture research specialists have been looking at the stocking standards that deal with the level of deciduous plants and the associated free growing levels of conifers so that the forest companies can meet their commitments.

Ongoing research is showing that using herbicides may not be achieving the intended results and collateral damage may often create many negative consequences.

Back in 2011 Mark Hume in a Globe and Mail article discussed growing concerns about the possible impact of glyphosate (the main constituent of Roundup) on frogs and other animals.

In 2008, a B.C. Ministry of Environment report concluded that glyphosate is “potentially highly toxic for many amphibian species.”

Read More: COLUMNS: The downside of being more efficient

In 2009, the Forest Practices Board noted in a report that glyphosate has been sprayed into wetlands, causing possible damage to amphibians, “however, the level of risk has not been fully assessed.”

Despite the concerns raised by those two reports, there haven’t been any follow up studies.

But Suzanne Simard, a Forest Science professor at the University of B.C., says the use of herbicides is misguided.

Her research has found that conifer forests don’t do better when the broadleaf plants are killed off.

The assumption was that spraying boosted the growth of conifers, because the competing plants were killed off.

But in the three decades the practice has been going on, there has been little effort made to confirm the results.

Now, Prof. Simard is studying just that, and finding that nature turns out to be more complicated than a lot of people thought.

“I was looking at it to see whether or not applying these herbicides actually achieved the goals the foresters were setting out to achieve … which was to improve the growth of crop conifers. And I found that, generally, it’s not that effective,” she said.

Now it turns out that it doesn’t help the conifers grow – which means the frogs, bees, and other forest species are being put at risk needlessly.

Read More: B.C. forest ministry cutting back on use of the herbicide glyphosate

Personal communication with some local silviculture specialists confirms many of the above observations.

The problem is that herbicides are viewed as a quick, easy, cost effective way of establishing conifer trees, but more and more research seems to show otherwise.

Susan Woermke has many years of silviculture experience in the interior of the province and has arrived at the following conclusions.

“We do not need to use herbicides as there are other means of effective establishment: timely silviculture practices and site-specific prescriptions may be utilized as a means of meeting legal obligations without undue cost.”

In her experience, conifers may also suffer growth defects contrary to the claims of herbicide manufactures.

A study in eastern Canadian forests also described similar conclusions as in this province.

The conclusion was that stocking of commercial species without the use of herbicides was superior and it was recommended that the government cease to fund herbicide use in Nova Scotia, and consider banning their use on Crown land.

Jim Hilton is a professional agrologist and forester who has lived and worked in the Cariboo Chilcotin for the past 40 years.

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

North District RCMP are urging the public's assistance in locating Prince George resident Amber Wuetz, 25, last seen Oct. 18 in the Canim Mahood Lake area north of 100 Mile House. (Photo submitted)
Prince George woman confirmed dead, foul play not suspected

Police confirm Amber Wuertz was found deceased on Oct. 31

As winter gets underway the city is reminding residents of its snow and icy policy and the role residents have in clearing sidewalks and keeping vehicles and carts off the street when snow plows are in the area. (Monica Lamb-Yorski file photo - Williams Lake Tribune)
Williams Lake reminds residents of snow and ice policy requirements

Clearing of snow and ice from sidewalks is responsiblity of property owners

Masks are now officially mandatory in all City of Campbell River facilities. (Black Press File Photo)
Interior Health reports 49 new COVID-19 cases overnight

302 cases remain active; two in hospital

Quesnel Kangaroos forward Justin Fulton (17) fires the puck on Stampeders goaltender Matt Brenner’s (37) during a contest at the West Fraser Centre in Quesnel last season. (Sasha Sefter - Quesnel Cariboo Observer)
Stamps, Central Interior Hockey League, cancel 2020/21 season

The team said it would like to thank the community, its fans, volunteers and sponsors

Provincial health officer Dr. Bonnie Henry updates B.C.’s COVID-19 situation at the B.C. legislature, Nov. 23, 2020. (B.C. government)
B.C. daily COVID-19 cases hits record 941 on Tuesday

Further restrictions on indoor exercise take effect

A fentanyl test strip is used at Vancouver Coastal Health in Vancouver, Tuesday, January, 21, 2020. The test strips will be made available to drug users to ensure that their drugs are safe and free of Fentanyl. THE CANADIAN PRESS/Jonathan Hayward
Drug overdoses lead to 5 deaths each day in October; drug toxicity continues to increase

COVID-19 crisis continues to exacerbate the overdose crisis

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

An employee of the Adventure Hotel was taken to hospital on Nov. 20 after she confronted a customer of Empire Coffee about not wearing a mask. File photo.
Nelson hotel employee suffers heart attack after being assaulted in anti-mask incident

An accountant at the Adventure Hotel is in hospital in Kelowna

Damien Smith, with father Thomas Smith, is “frozen” with joy as he watches a special message Deadpool star Ryan Reynolds recorded for Damien’s 9th birthday on Tuesday, Nov. 24, 2020. (Contributed)
Shuswap boy celebrates 9th birthday with family, community and Ryan Reynolds

People from around the world send birthday cards showing young Canoe resident he’s not alone

Join Black Press Media and Do Some Good
Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

(Ashley Wadhwani/Black Press Media)
Refuse to follow B.C.’s mask mandate? Face a $230 fine

Masks are now required to be worn by all British Columbians, 12 years and older

Prime Minister Justin Trudeau speak to the media about the COVID-19 virus outside Rideau Cottage in Ottawa, Friday, Nov. 20, 2020. THE CANADIAN PRESS/Adrian Wyld
Canada’s inability to manufacture vaccines in-house will delay distribution: Trudeau

First doses of COVID-19 vaccine expected in first few months of 2021, prime minister says

Beaver Creek RCMP Cpl. Robert Drapeau, left to right, Gary Bath, Lynn Marchessault, Payton Marchessault, Rebecca Marchessault and Tim Marchessault pose in this recent handout photo near the Canada-U.S. border crossing near Beaver Creek, Yukon. A family reunion trip for the woman from Georgia that left them stranded ended on a bright note when Bath drove them to the Alaskan border following an appeal for help. THE CANADIAN PRESS/HO, Gary Bath *MANDATORY CREDIT*
Help from B.C. man allows American family to reunite in Alaska

Lynn Marchessault drove from Georgia to the Alaska border to join her husband, who serves in U.S. military

Most Read