HERBICIDE USE AND FORESTRY

May 2013

What are “herbicides”?

Herbicides are a class of pesticides used to control 

unwanted plants. Herbicides are used in agriculture, 

residential and urban areas, forestry, industrial sites, 

railroads, and other settings.

How are herbicides used in forestry? 

Oregon’s Forest Practices Act requires planting of tree 

seedlings within two years after a timber harvest. To 

meet this objective, both families with small properties 

and large industrial companies use herbicides to 

control unwanted vegetation so tree seedlings can 

receive adequate water, nutrients and light. Herbicides 

are also used by many forest landowners to control 

damaging, invasive plants such as knotweed, which 

can take over streamside areas and destroy native 

plants. 

Some landowners see herbicides as the most costeffective means of achieving reforestation goals after 

logging or fire, and for converting brushy land to 

forested land; other landowners choose to meet their 

goals without using herbicides. Other tools available to 

control unwanted vegetation include cutting brush by 

hand or with power tools, grubbing grass sod from 

around individual trees, mowing, and placing mulch 

mats around individual trees.

How often are herbicides used in forestry?

Forest landowners are responsible for only 4 percent of 

all pesticides (including herbicides) used every year in 

Oregon. In Western Oregon forests, herbicides are 

typically applied in the first two or three years after 

harvest. Because of different management methods on 

the slower-growing forests in eastern Oregon, 

herbicides are used much less in that region of the 

state. 

What laws regulate forest herbicide use?

All pesticides used in the United States must be 

registered with the U.S. Environmental Protection 

Agency (EPA) and must carry federally approved 

labels describing permitted uses and appropriate 

protection measures. To be registered, pesticides must 

be tested for effects on humans and the environment. 

In Oregon, pesticide sellers and applicators must also 

comply with the state's Pesticide Control law (Oregon 

Revised Statute Chapter 634) which requires state 

product registration and applicator licensing, and 

prohibits faulty, careless or negligent applications. 

Users of pesticides on forest land must follow an extra 

layer natural resource protection laws in the Oregon 

Forest Practices Act, administered by the Oregon 

Department of Forestry. The Forest Practices Act 
requires operators to protect soil, air, fish, wildlife, and 

water quality through measures that include:

• Preventing leaks and spills

• Avoiding aerial herbicide applications within 

60 feet of fish-use streams or drinking water 

streams, and avoiding ground-based 

applications within 10 feet of those streams.

• Leaving and protecting trees and plants along 

streams following logging.

The Department of Forestry works with landowners, 

loggers, and pesticide applicators to help them comply 

with forest practice rules; in most cases, compliance is 

achieved voluntarily. In a few instance, enforcement is 

needed. Under rules administered by the Departments 

of Forestry and Environmental Quality, if a spill 

occurs on forestland, those responsible are required to 

report the incident and take any necessary action to 

contain and clean up the chemical.

Measures protect water quality

Forestry laws and rules have had demonstrated success 

in protecting streams [2000 State of the Environment 

Report for the Oregon Progress Board; produced by 

Oregon State University].

The Department has conducted monitoring efforts on 

pesticides since the 1970’s, including: 

• Frequent sampling downstream of spray 

operations between 1980-1987. 

• Specific monitoring of projects occurring in 

1992, 1993, and 2000.

• A pesticides best management practice (BMP) 

compliance element within a larger 2002 best 

management practice study.

In nearly all cases, either there were no detectable 

residues or the residues were below levels expected to 

be harmful to humans, fish, wildlife, or riparian 

vegetation. 

How can I get information on planned 

herbicide applications?

Before doing a pesticide application on forestland, the 

applicator must file a notification of operations with 

the Oregon Department of Forestry. The notification 

describes the who, what, when, where, and how of the 

planned application. The department maintains a 

database of the notification information from this 

system available to the public upon request. To find 

out what forest chemical applications, or other forest 

operations, are planned in your area, sign up for ODF's 

subscription service (there is a fee for this service). 

To sign up, call or visit your nearest ODF office or 

ODF's Salem headquarters (503-945-7200). You can 

also find the subscription form and more information 

about the FACTS subscription service by visiting the 

department Website at http://egov.oregon.gov/ODF/

(Click on “Private Forests” then select “Forest 

Operations” in the upper right corner of the screen, and 

then “FACTS Data”).

What if I think a violation of the law has 

occurred?

If you think a violation of the law has occurred, please 

contact the local Oregon Department of Forestry 

office. Staff there will investigate your report and 

provide information back to you on their findings.

For additional information:

• Oregon Department of Agriculture (Oregon’s lead 

agency for pesticide use),

http://www.oregon.gov/ODA/PEST/www.oregon.g

ov/ODA/PEST/

• U.S. Department of Environmental Quality,

"http://www.epa.gov/pesticides/"www.epa.gov/pest

icides/

• The Pesticide Analytical and Response Center,

"http://www.oregon.gov/ODA/PEST/pare.shtml" 

www.oregon.gov/ODA/PEST/pare.shtml

• Oregon Department of Environmental Quality,

"http://www.oregon.gov/DEQ/"www.oregon.gov/D

EQ/