Northwest Office

Northwest Regions

Herbicides are Part of the Forest Manager’s Toolkit

By Heather Hansen

It is not news to most foresters that the use of herbicides in forestry has come under attack by the public in recent years. Yet, herbicide use remains the most effective way to control invasive plants and protect newly planted trees from competition so they are free to grow.

In Washington and Oregon, the level of fear and community unrest over the aerial application of herbicides over timberland has increased in recent years. Media coverage of glyphosate and related lawsuits has increased the anxiety level considerably. For those who get their scientific knowledge from TV, which is most people, Round-up sounds like a very scary product. Many people believe any exposure to it is likely to cause cancer. They also do not understand how a helicopter could possibly control where spray droplets land when they hit the earth. If you do not understand how it works, it seems logical that what comes out of the nozzles could spread widely and land almost anywhere. I have listened to citizens describe this fear. Many sincerely believe that an application, miles from their home, could affect them, their pets, livestock, and garden. In reality, a helicopter pilot has a great deal of control over where the herbicide lands. The application is guided by GPS and the herbicide is laid down within approved boundaries. Allowing the herbicide to drift out of the intended application site is a violation of the law.

Another factor contributing to increased apprehension is that many members of the public no longer trust the Environmental Protection Agency (EPA). They are unaware that there are career scientists who have worked on pesticide research through multiple administrations. The pesticide registration process is set in law and has not been changed by the current administration. They do not know that the EPA has one of the most comprehensive pesticide registration systems in the world. Over 120 tests are required to ensure products will not harm people or the environment. Every time a concern is raised, more testing can be required, and more restrictions added to the label.

The public is also unaware that the decision to use herbicides is not made lightly by landowners. Purchasing herbicides is expensive. Applicators must pass a test and be licensed by the state department of agriculture. Aerial applicators are also licensed and regulated by the Federal Aviation Administration. 

The Washington Conservation Voters just released their 2020-2024 political campaign, which includes a goal of phasing out the “use of the most dangerous pesticides in forest land management.” This goal is based on emotion and myth, not science. Pesticides used in forestland management are almost all herbicides. Most herbicides are non-toxic to humans, other mammals, fish, and insects. It is unclear what criteria they may use to determine something is dangerous. It is even less clear how they would propose to control noxious weeds, which can destroy habitat, or how they would create an environment conducive to tree growth. The fact is that without herbicides, it is very difficult to reestablish trees or control invasive plant species.

Communicate, communicate, communicate

The second most important part of a herbicide application is communicating with neighbors. The most important part of the application will always be to follow the label and ensure there is no drift.

Herbicides are applied via several methods, such as helicopter, backpack sprayer,
or by a pickup truck. Truck photo courtesy of Glenn Miller

Meeting with neighbors takes time, but it’s time well spent. It can minimize complaints and develop friends. The more information people have about an application, the more likely they are to remain calm. People want to be listened to. They want to know you care about them and their concerns. Most people are reasonable when their questions are answered. Many timber companies contact neighbors prior to beginning a harvest operation. When it comes time to spray, someone in the company probably already knows which neighbors are likely to be concerned.

It is also important to reach out to county commissioners or council members. They will hear from concerned citizens. It is important for them to also know that you care about the land you manage and are protecting habitat by controlling invasive plants. Helping them understand state and federal regulations for herbicide use will also help. Establishing and maintaining open lines of communication will help keep herbicides as an available tool.

Concern about herbicide use has also increased with state legislators. Most legislators are unaware that every aspect of pesticide use is regulated by either the state or federal government. Reaching out early and explaining what you do, why you do it, and how it is regulated will reduce their level of concern.

In 2019, Washington Senate Bill 5597 created a work group on aerial pesticide applications in forestlands. The work group developed recommendations for improving the best management practices for aerial application of pesticides on state and private forestlands. In 2020, Senate Bill 6488 was introduced by the same senator to implement the work group report. SB 6488 failed to pass, but the work group report remains in place. Much of the report focused on improved communication with neighbors in a broad sense including clarifying existing buffers, communicating best management practices and improving signage.

In addition to outreach efforts to allay the public’s concerns, land managers may wish to consider other application methods. In areas where citizen concern has been especially vocal, some companies have increased the use of backpack spraying rather than aerial application. This can be a good strategy for small units near roads and homes. However, backpack spraying is much more expensive and less effective. There is also the potential for workers to be injured when walking on uneven terrain.

What does the future hold regarding the public’s acceptance of herbicide use? Citizen concern is unlikely to diminish. The economic crisis state budgets will face because of COVID-19 may result in less action related to pesticides as legislators struggle to keep schools open and social networks in place. However, the budget crisis will not stop the true believers who want to stop pesticide use. The best way to stop anti-pesticide proposals from gaining traction is to speak to neighbors, elected officials, and community leaders now. Make sure they understand how pesticides are regulated. Make sure they know your goal is to help trees grow and reduce the destruction that invasive plants can cause if left unchecked. More than anything, make sure your audience knows you are listening. As one of my favorite foresters says, “Once they know you, it’s harder for them to hate you.”  u

Heather Hansen is the executive director of the Washington Friends of Farms & Forests in Olympia, Washington. She can be reached at 360-705-2040 or

Back to Table of Contents                    Next article