In 2015, the International Association for the Research on Cancer (IARC) classified glyphosate, the active ingredient in RoundUp, as a probable carcinogen. Following IARC’s decision, many U.S. local authorities have passed pesticide bans or integrated pest management (IPM) policies for their landscapes, fields and grounds.
Glyphosate is the most used herbicide for invasive species management in natural areas.[1] The amount of glyphosate used to control invasive weeds nearly triples the application of the next most frequently used herbicide Triclopyr. Triclopyr and other herbicides used for invasive weeds such as imazapyr, clopyralid and 2,4-D have their own subset of environmental and human health risks. Communities seeking alternatives for glyphosate would likely not view these other products as “safe”.
Cities moving to curtail glyphosate and other synthetic pesticide use need access to alternative, vetted, safe and effective strategies.
[1] Hawkins, C., C. Hanson, & D. Sells (2019). Glyphosate: Response to comments, usage, and benefits. US EPA.
The MGG Lawn & Land Forum began exploring glyphosate alternatives to invasive weed management in 2019 thanks to funding from the Illinois Department of Natural Resources Coastal Management Program.
We can limit or even eliminate glyphosate use in parks, natural areas and landscapes, but we need plans that go further than merely selecting organic or reduced risk weed products. Comprehensive plans will help native or desirable vegetation grow instead of invasive or undesirable vegetation.
During the Forum’s “Viable and Safe Alternatives to Glyphosate” webinar, Natural Communities, LLC’s Chief Ecological Officer Nick Fuller shared Jim Collins' Flywheel Effect approach that is very popular in business and entrepreneur circles. Historically, industry used flywheels to provide continuous power. Rotating a large flywheel takes significant energy at first, but the flywheel builds up momentum from past rotations and eventually rotates rapidly with little additional input from an external or supplemental energy source.
Fuller said Collins' Flywheel Effect relates to weed control in many ways. Soil, weather and human intervention conditions in many urban landscapes across the Midwest favor invasive and undesirable vegetation growth. Overcoming these condition barriers will take significant effort over the first few years. However, Fuller says the time and resources spent early on will achieve optimal outcomes with limited synthetic herbicides, “When you’re into year five, your project should be pretty solid, but you can’t abandon the flywheel at that point. Every year you keep building that momentum to help defend against invasive species and build a more resilient and more functional ecosystem.”
According to Fuller, landscape managers can achieve a “self-rotating” flywheel by investing time and resources into four flywheel spokes of (1) Investigation, Planning and Prevention, (2) Plant and Seed Selection, (3) Alternative Weed Control Products and Practices and (4) Evaluation and Improvement
The restoration work of V3 Companies at the Gray Willows Wetland Mitigation Bank in Campton Hills, IL exemplifies the ability of the Flywheel Approach to limit weed control and grow biologically diverse ecosystems. V3 Companies initiated Gray Willows restoration work in 2015 when ecologist George Milner visited the site to investigate the soils and existing vegetation. Milner explained, “Gray Willows has different plant communities that each require a custom recipe for improvement.”
The site’s existing plant communities included a 12-acre turf grass area used for golfing with only 10 different native plant species, a monoculture agricultural field, an oak woodland with an understory of buckthorn, honeysuckle and chervil and a wetland site dominated by the invasive weed reed-canary grass. V3 Companies final design plan for Gray Willows designated 32 acres from mostly the turf grass and agricultural field for wetland reestablishment based on their hydric soils and water draining into the two landscapes. The plan, also, detailed enhancement measures for the 10 acre reed-canary grass dominated wetland.
In 2019, V3 Companies planted seven custom native plug mixes at all the wetlands and three different seed mixes in the more saturated and dry wetlands. From 2019 through 2023, Milner will monitor the plantings to see how well they perform, “We have to do an annual report where you evaluate your standards and then recommend necessary activities for next year.”
The wetland seeds and plugs planted in 2019 have performed well thanks to Milner’s attention to each of the Flywheel spokes. Milner highlighted two data points that proved favorable results in all three wetland areas. First, transect monitoring found a low Absolute Non-Native Species Cover at each wetland: 1.1% at the former agricultural site, 1.8% at the former turf grass site and 5% at the existing wetland site. The U.S. Army Corps of Engineers sets a 5% or below goal for the Absolute Non-Native Species Cover for wetland mitigation banks. Second, the Native Perennial Dominance Measure (RIV) found high native perennial plant density at each wetland: 88.0% at the former agricultural site, 89.2% at the former turfgrass site and 65.2% for the existing wetland site. Any RIV above 75% is acceptable for V3 Companies.
Milner said these results reduce the need for herbicide in 2021 and the future, “The more native perennial species you have, the more stable your community is and the more resistant it is to weed pressure.”
“Partnerships are so important to the work that we do,” said Laurie Schneider of the Pollinator Friendly Alliance. “Partnerships are how others can learn about best stewardship practices for pollinators and learn how to support a clean environment.”
In 2018, the Pollinator Friendly Alliance partnered with Dan MacSwain of Washington County Public Works Department to restore the 14-acre Pine Point Park without pesticides. Schneider and MacSwain used a combination of conservation mowing, burning and winter inter-seeding to transition the corn field on-site to a grassland and native plant sanctuary to attract pollinators.
Washington County Parks and the Pollinator Friendly Alliance involves, engages and educates the community by offering citizen science and ecology programs at Pine Point Park and the County’s other 4700 acres. These programs include tours of the goats that graze on park unwanted vegetation such as buckthorn, hand seeding native prairie at the parks and manual removal of unwanted vegetation.
“The community loves it, it’s a source of community pride and the best way for people to learn and get on board,” Schneider said.
The Pollinator Friendly Alliance and Washington County have furthered their collaboration by adopting an IPM plan for all of Washington County’s parkland that aligns with the Flywheel Invasive Weed Management approach. The IPM plan maps all turfgrass areas that receive mowing and herbicide treatments to identify less visible areas where Washington County could save time and resources by limiting management.
“If you make a plan, you will see way less herbicide used across your system,” said MacSwain