As the COVID-19 pandemic has resulted in budget cuts for a number of vegetation management programs across the country, many professionals are being forced to do more with less. However, with the right products and strategies in place, vegetation managers can make the most of available funding to help protect utility infrastructure and create healthy ecosystems throughout right-of-way corridors.
When an interruption in utility service occurs, the residual effects are far-reaching. Businesses face economic losses, dissatisfied homeowners lose a sense of security and utility companies are forced to bear the financial weight of power loss and restoration. Common causes of service interruptions include automotive accidents, digging projects, lightning and high power demands. However, no cause of service failure is more common than vegetation-related incidents.
When trees and other forms of woody plant species are allowed to develop within utility rights-of-way, they pose the constant threat of either growing or falling into nearby power lines. In the past, vegetation managers used mechanical control methods like mowing to help utility companies avoid these unfortunate scenarios. But in recent years, industry research has shown that alternative methods of control can effectively eliminate problematic vegetation to reduce maintenance costs and improve system reliability. And as lower levels of productivity in the manufacturing industry have reduced utility demands in the wake of the COVID-19 pandemic, subsequent budget cuts have made the efficient use of available funding all the more imperative.
When vegetation management programs lose financial support, the maintenance required to effectively control incompatible vegetation often gets delayed. Since trees and other woody plants can grow exponentially from one year to the next, utility managers must employ effective treatment strategies to adequately address threats to electrical transmission reliability. In fact, studies conducted by Corteva Agriscience have shown that leaving incompatible vegetation untreated for a single year can have significant financial consequences for management programs.
“Brush species can grow anywhere from 20% to 40% in size annually,” says Chad Cummings, field scientist with Corteva Agriscience. “The field research we’ve conducted has revealed that delaying routine maintenance by a single season can double the cost.”
As a method of nonselective control, mowing is as effective at removing target species as it is on native plant communities. Moreover, mowing is regularly required to manage regrowth, which leads to recurring costs that can cripple vegetation management programs during periods of budgetary lulls.
“Practitioners looking to improve cost efficiency and support the development of biodiverse ecosystems are encouraged to consider the use of selective herbicides as part of an Integrated Vegetation Management program,” Cummings says.
Selective and Effective
The U.S. Environmental Protection Agency defines Integrated Vegetation Management (IVM) as a practice that promotes desirable, stable and low-growing plant communities that will resist the invasion of tall-growing tree species through appropriate, environmentally sound and cost-effective methods of control. It represents an approach to vegetation management that supports herbaceous plant diversity, effective control of incompatible plant species, lower maintenance costs and habitat improvements for various wildlife species. For vegetation managers working throughout utility rights-of-way, IVM strategies are used to develop low-growing, stable plant communities consisting of shrub or grass species that promote system reliability and mitigate risks associated with fire hazards or limited site accessibility. Utilities practicing IVM have even found ways to include their beneficial management practices in corporate Environmental, Social and Governance (ESG) reporting.
Effective methods of control that align with IVM practices include biological, chemical, cultural, mechanical and manual treatments. However, few are as environmentally friendly as the use of selective herbicides.
“When applied properly, selective herbicides can eliminate incompatible plant species with minimal effect on surrounding native plant communities,” Cummings says. “Whereas mowing or the use of nonselective herbicides can wipe out all plant species in a treated area, selective herbicides support the development of compatible vegetation, enhance biodiverse ecosystems and significantly reduce costs associated with long-term maintenance requirements.”
Each foliar season, vegetation managers use selective herbicides for a variety of directed, spot and broadcast foliar applications. For areas with lower stem densities or hazardous terrain, backpack equipment is most commonly used to execute low-volume foliar applications. Comparatively, UTV or truck-mounted equipment is commonly used for hydraulic foliar applications, and large tractor-mounted equipment is typically used for broadcast applications, which uniformly apply treatments in areas where increased stem densities are present. As some herbicides are more effective at certain points in the treatment season than others, referencing the product label for application methods, use directions and rate restrictions prior to use is always recommended. But when the right herbicide is used and applications are timed correctly, the results can significantly benefit vegetation management programs and the environment.
Embracing Results and Roadblocks
As the electrical generation and transmission arm for 11 distribution co-ops throughout the state of Mississippi, Cooperative Energy has used selective herbicides like Opensight®, Garlon® 4 Ultra and Vastlan® as part of its vegetation management program since 2008. The co-op has supplemented its herbicide treatments with routine mowing to treat some of the region’s most prevalent brush species, including sweetgum, volunteer pine and Chinese tallow. But providing ample clearance from power lines isn’t the only benefit that Cooperative Energy has generated since it started using selective herbicides. Six counties in its service territory are considered prime habitat for the extreme western range of gopher tortoise, and the optimum control of incompatible plant species has created an environment in which the endangered species can thrive.
“Herbicide applications opened up the entire corridor,” says Wes Graham, right-of-way manager and field biologist at Cooperative Energy. “Over the course of three years, we saw a tremendous reduction in the amount of gopher tortoise burrows in the centerline. They started moving toward the edges of the rights-of-way, and the population increased by 32% where prime habitat existed.”
In addition to improving critical habitat for the gopher tortoise, Cooperative Energy has placed heightened emphasis on the use of IVM practices to support the creation of early successional habitat for pollinators, which help to deliver about one-third of all food and beverages around the globe. And while the opportunity exists for utilities across the country to have a similar impact on the environment, a variety of roadblocks can pose a threat to their annual productivity.
Issues like inclement weather, budget restrictions, equipment access and a diminished workforce can keep vegetation managers from treating all desired sites each year. Fortunately, alternative strategies allow practitioners to circumvent these barriers by extending the treatment season and minimizing the threat that incompatible vegetation poses to the environment and electrical transmission reliability.
Dormant-Season Treatments
Foliar herbicide treatments comprise the vast majority of herbicide applications used by vegetation managers to control incompatible tree species. At times, this treatment window can become too narrow, and without alternative control methods in place, incompatible species can develop quickly and offset program efficiency. But thanks to alternative applications like low-volume basal bark, basal cut-stump and dormant-stem treatments, practitioners are able to use selective herbicides from fall leaf senescence through spring bud break to either extend or kick-start each treatment season. Employing these alternative methods of control can help vegetation managers make the most of fiscal budgets and impede the development of target species from one year to the next.
Taking It One Step Further
As a leader in wildlife conservation, the National Wild Turkey Federation (NWTF) recognizes the immense potential of IVM practices. Having recently developed the Energy for Wildlife Rights of Way Habitat Endorsement Program, NWTF works alongside energy partners, surface landowners and a variety of stakeholders to support habitat enhancement throughout right-of-way corridors.
Energy companies that wish to participate in the program are encouraged to enroll their rights-of-way where IVM is practiced to the Integrated Habitat Management (IHM) level. By enhancing the development and maintenance of early successional habitat, IHM is an elevated approach to vegetation management that provides a variety of benefits to wildlife and pollinator species. As a key program partner of the Energy for Wildlife Program, Corteva Agriscience has continued its commitment to promoting the use of IVM practices that provide a suite of ecosystem benefits, including increased plant biodiversity and habitat improvements for pollinator and wildlife species.
“Corteva Agriscience is honored and excited to partner on such a groundbreaking initiative,” says Damon Palmer, U.S. Pasture and Land Management leader at Corteva Agriscience. “As an advocate for an Integrated Vegetation Management approach, the NWTF understands the importance of a formalized program to help companies achieve enhanced habitat using proper maintenance practices.”
Healthier ecosystems and electrical transmission reliability aren’t the only positive results for energy companies that practice IVM and enroll in the Energy for Wildlife Program. In addition to supporting the development of critical habitat for a variety of pollinator and wildlife species, different levels of participation yield marketing benefits to new and current members. For more information, those interested in the program’s perks and qualification requirements are encouraged to visit efw.nwtf.org.
Creating a Sustainable Future
A number of strategies can be used to control incompatible vegetation that threatens utility infrastructure and impedes the development of biodiverse habitats. But by protecting native plant communities and targeting only populations of incompatible plant species, IVM programs featuring selective herbicide applications can support the development of compatible plant communities to create a biological barrier against woody plant establishment. As populations of incompatible species diminish, less labor and maintenance is required as a result. This provides a sustainable and cost-effective solution that allows vegetation managers to improve their environmental impact while ensuring the long-term reliability of electrical service for the businesses and public that depend upon it most.
