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Facts and Fallacies on Right-of-Way Herbicides
By H. Dennis P. Ryan
There has been a considerable amount of debate recently, at public meetings and in the press, about the use of herbicides by the utility industry. The main thrust of this debate has been that all herbicides are bad for people and the environment. Citizens groups, such as Toxins Action Center , Herbicide Free Power Lines and others, are expressing their concerns to the utilities and their state government. Most of these groups list a variety of reasons why herbicides / pesticides should not be used, including:
1. The testing of approved herbicides is insufficient and outdated.
2. Chemicals in combination are more toxic than individually, yet they are tested individually.
3. Crop damage from over-spraying has occurred and private wells are at risk.
4 . People use trails that cross power lines where spraying is not posted.
5. Childhood cancer and asthma are on the rise.
This list could go on, but one gets the gist of their feelings. Some of their concerns have some basis in fact—drift to non-target areas is unacceptable and sprayed areas could easily be posted. Many of the concerns, however, show a complete lack of faith in both corporate America and in government agencies. These beliefs can lead to very heated public meetings at which all involved parties—utility companies and anti-pesticide groups—seem to leave the meetings upset and confused.
“ ... the [ Worthington ] Conservation Commission, which called the meeting, said it is satisfied that the plan is safe and is not convinced that the people who have expressed their concern speak for the majority of residents. In response, MW is launching a petition drive against the use of herbicides with the help of the Toxins Action Center .” Berkshire Gazette 3-22-99
What most of the people protesting chemical Right-of-Way (ROW) management do not realize is that the utility industry is required by law and the threat of litigation to keep vegetation away from their utility wires. Electric lines that come in contact with trees cause reliability and safety problems for the utility company and the general public. A tree growing in contact with electrical wires can conduct electricity. People on the ground or children climbing in a tree adjacent to electric lines have come in contact with the electricity and been electrocuted. The state of California has had many cases where forest fires were the result of conflicts with electric wires.
Reliability is also a major issue. Today, the public and businesses are more dependent than ever on a steady and reliable flow of electricity. When the lights go out, so do the computers, medical apparatus, traffic signals and the air traffic control systems. The bottom line is the utility industry is required to keep the electricity flowing both safely and reliably. If they fail, they are held accountable.
Trying to have an open-minded debate concerning herbicides is similar to trying to review abortion or gun control. There are still people in the business—fortunately, very few—who believe they should be able to spray whatever they want, whenever they want. At the opposite end are citizens who believe all pesticides are bad and should be banned. Quite frankly, advocates of responsible pesticide use are not going to win the debate with either of these minority groups. Their minds are closed, and they do not want to be confused by the facts. The industry needs to educate both the ROW managers and the general public, most of whom are in the middle and open to factual information.
There are basically three ways to maintain a ROW—mechanical, chemical or biological / integrated. Each of these systems has advantages and disadvantages with respect to financial considerations, environmental effects and worker safety.
Mechanical
Maintaining a ROW using mechanical means is as old as utility wires, starting with telegraph lines in the late 1800s.
With saws, ROW technicians can remove individual plants and thus be selective. On level terrain with many stems, this would be an expensive way to remove tall trees. But on steep or rocky areas, this may be the only way to do the job. Unfortunately, working on a steep slope with a chain saw or brush cutter—especially in a rocky area—can be very dangerous work for a ROW technician.
Mowing can be more cost effective on level ground, but it leaves the site looking like a war zone. The biggest problem with using a mechanical means to maintain a ROW is the response of the trees to being cut down, as a result of the top / root ratio. Trees re-sprout from the cut stump because the roots are left healthy and intact in the ground. Farmers and foresters have used this system for centuries to produce fast-growing firewood. The practice is called coppice. Tree and woody brush density is increased as a result of not killing the root system. If their root systems are not controlled, it is not uncommon for tall trees such as oak, poplar or maple to grow more than ten feet in the first year following mechanical cutting.
While mechanical cutting needs to be used on some sites, in most situations it is not a first choice because of the problems it can produce.
Chemical
Chemical herbicide treatments became widely used following World War II. Postwar America was very proud of new cures for old problems—antibiotics for our children, DDT to control gypsy moths and 2, 4-D to manage our ROWs. Obviously, everything did not work out quite the way it was planned. Pesticide users made mistakes then, but herbicides properly used are a tool that can maintain ROW vegetation in a financially acceptable, safe and environmentally sound manner.
There are currently three medium- to low-density programs being used by utility systems today to maintain ROW lines.
This technique, often called “cut & squirt” by the ROW technicians, is especially suited for individual tree removal alongside ROW lines or in populated areas. It eliminates leaving dead tree skeletons standing. The tree worker fells the tree and the freshly cut stump surface is treated with a herbicide. The treatment is usually done with a hand sprayer, employing very little active ingredient per stump. The result is that the roots are killed and there is very little re-sprouting. Pre-mixed and no-freeze formulations are available for year-round use. Most formulations contain a dye that make it easy to see where the herbicides have been applied.
This is an effective treatment method that allows the technician to target only problem plants that could grow up into the lines without affecting neighboring, low-growing shrubs, grasses or herbaceous plants. Re-sprouting is controlled and this system can be used year-round, conditions permitting. One disadvantage is that this technique leaves dead vegetation standing.
When many of us think of foliar sprays, we remember the old days of total brownouts along the entire ROW. Fortunately, most utility companies today do not advocate this practice. If your ROW is located in an area where you can tolerate minimal brownout, then low-volume foliar treatments can be used effectively to control low to medium vegetation.
The ROW technician usually applies the herbicide to individual plants using a backpack sprayer at close range. This system allows for selective spraying, which protects non-target plants while killing the roots of tall-growing trees.
The above programs can be used in sensitive areas, will kill the roots of tall-growing trees and are cost effective.
Biological / Integrated
Most utility ROW managers and the general public would agree that the best method to use on a ROW is a biological or integrated approach. Managing a ROW in this manner encourages the creation of dense, low-growing plant communities. Biodiverse plants such as grasses, ferns, herbaceous wildflowers, blueberry and bayberry bushes and low-growing trees like dogwoods are encouraged. Tall-growing trees that have the potential to grow up into the ROW lines would be aggressively discouraged.
The methods used to control tall-growing trees would be mechanical and chemical. Tall trees are removed to encourage low, dense growth. This type of management reduces the seeding in of new trees because the groundcover does not allow the light necessary for trees’ seeds to germinate.
Once this dense growth of low plants has been established, it is very easy to maintain the dense ground vegetation with periodic treatments using low-volume herbicides. The chemicals used to maintain a ROW in this manner would be less than what the average suburban homeowner spreads on his lawn.
In analyzing the use of herbicides on a ROW, one has to take into consideration the cost / benefit of using herbicides and the cost / benefit of not using herbicides. For every cost—financial, environmental, worker safety—there should be a benefit that outweighs any negative aspects of the treatment. Yet one has to take into consideration that sometimes the cost of not doing something is steeper in the same areas than doing the debated treatment. Remember, the utility industry is required by law to keep their electric lines safe and reliable. So, if herbicide treatments are banned, how will they keep electricity flowing safely and reliably, and what will alternative treatments cost electric consumers, utility workers and the environment?
If one assumes that the ultimate goal of the concerned public and ROW managers is to manage ROWs based on the biological or integrated approach, then one needs to look at the cost / benefit ratio based on that strategy. Integrated ROW management can help improve public relations and, at the same time, help the utility manager in the following ways:
1. Aesthetics
A ROW containing trees and bushes that is mowed will look terrible, especially when compared to a ROW that is well maintained with low-volume herbicides. While a mowed ROW may make the utility company happy, most of the general public will find the view upsetting.
2 . Safety
Worker safety is or should be a priority with all utility companies and contractors. Working with chain saws and mowers on a rough site can be very difficult and dangerous for workers. Integrated ROW management will increase worker safety and reduce serious accidents.
3. Environmental issues
Water: One of the public’s major concerns is how herbicides will affect water quality. There are herbicides that are registered for use near and on water. If the ROW is in the vicinity of water, situations may arise where conventional herbicides cannot be used and alternative methods are needed. If water is an issue, then the ROW manager will need to consider a material that is compatible with the specific site.
Keep in mind that, in most cases, the alternative to not using herbicides is to mow the site. Mowing can result in rutting and erosion problems, leading to a degradation of water quality of a different sort.
Birds & animals: When grasses and ground-hugging plants flourish, wildlife does too. Anyone who has spent time outdoors and has flushed a deer from its bed or had the pleasure of watching rare birds or butterflies knows that you will not find this biodiverse habitat on a mowed ROW.
The fall 1997 issue of News from Hudsonia had an article entitled “Untapped Power: Rare Species in Utility Corridors, which noted: “Rare species and natural communities on and near power line cuts (ROW) would benefit greatly from information-sharing and cooperation among amateur naturalists, research scientists, and utility management decision-makers. Nature lovers should not shy away from utility corridors in the belief that they are too disturbed to be interesting. Indeed, we may find that many populations of rare species will yet be discovered in the unlikely context of power line paths.”
Environmental concerns play a more prominent role than ever in the day-to-day activities of a ROW manager. Society better understands the importance of protecting the quality of the environment and natural resources. But when the environmental site is a ROW, maintenance and ease of access are also important. The key to a successful ROW management program is to balance the needs of nature and the needs of the public to have an adequate supply of electricity.
Pesticides are tools, just like chain saws or lawn mowers. If used properly, ROW herbicides are safe for the ROW workers and are environmentally friendly. If used improperly by untrained or uncaring workers, they can become a problem for the worker and the environment.
When considering the use of a herbicide for ROW maintenance, one must weigh the total cost of using this tool—for the worker and the environment, as well as the bottom-line cost. Then weigh the cost of alternatives. Herbicides have a legitimate place in most ROW maintenance plans.
H. Dennis P. Ryan is a professor at the University of Massachusetts, Department of Natural Resources Conservation, in Amherst, Mass
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