All methods of forest weeding entail some risks. Some are measurable, such as frequency of accidents. Scientists can evaluate exposure-and to some extent, actual intake-of pesticides, exhaust fumes, fuels, and lubricants-and observe whether worker safety is affected. Evidence to date suggests physical injury while working in the woods is where greatest improvements in safety can be made, primarily related to falls, falling trees, bee stings, and chainsaw accidents.

Pesticide applicators must consider numerous factors. Treating a forest often entails applying herbicides over large areas. Definitions of treatment boundaries and stream buffers must be very clear. It is always wise for the applicator to avoid unnecessary exposure to all risks, including potentially harmful machines, tools, and chemicals, including fuels and lubricants. It is always wise to consult neighboring landowners before a major spray job, and to take the needed precautions to avoid chemical trespass. The benefits from judicious and well-planned herbicide use can be enormous and should not be jeopardized through poor public relations or careless application.

Restricted-use pesticides Atrazine and picloram (except in the products Pathway and Tordon RTU) are federally restricted-use herbicides. Both are low in mammalian toxicity but require special handling because of potential for water contamination and, in the case of picloram, high crop sensitivity. A state certified applicator's license is required for purchase and use of restricted-use products.

Besides federally restricted-use products, some forestry labeled products can have restricted uses in an individual state. A list of ingredients that have restricted uses in the Pacific Northwest are located in the beginning of this handbook. Users should consult the label and the respective state department of agriculture for additional restrictions.

Always follow directions on the herbicide label. The label is legally binding. The information in this handbook is not intended to be a complete guide to herbicide use. Before using any herbicide, read the label recommendations on the container. Before an herbicide can be recommended for a specific use, it must be thoroughly tested. Recommendations on the manufacturer's label, when followed, can prevent many problems arising from the wrong use of a chemical. Because some uses listed on labels can be marginally cost effective, they often are not discussed here, although they are legal. If you are uncertain about label interpretation, your dealer can help, or consult with your state department of agriculture for final determination.