Roads and noxious weeds seem to go hand in hand on most public lands in the United States. It is not easy to improve or maintain backcountry roads without spreading noxious weeds. This document includes recommendations for reducing or eliminating the spread of weeds during road maintenance. Recommendations are based on weed biology, road maintenance practices, and observations rather than actual research. Very little research has been conducted on this topic.

State governments have legally declared more than 500 invasive plants "noxious weeds" (Skinner, Smith, and Rice 2000). Plants are defined as noxious weeds if they are carriers or hosts of damaging insects or diseases or if they are overly aggressive, difficult to manage, parasitic, or poisonous. Most noxious weeds are not native to the United States. Many do not create problems in their native environments. For information on species that have been declared noxious in a particular State or area, contact the State department of agriculture noxious weed coordinator, or a county extension agent or noxious weed superintendent. All State noxious weed lists can be accessed through the INVADERS database (http://invader.dbs.umt.edu/). Click on State/Provincial Noxious Weed Lists and specify the State.