U.S. Forest Service analysts are looking for public comment on managing unwanted trees, brush and grasses in national forests.

The agency's Intermountain Region, headquartered in Ogden, is writing an environmental impact statement on various ways to control what foresters call "unproductive and unwanted vegetation."Programs covered by the statement are those intended to wipe out plants along roadsides, remove brush to improve tree growth, eliminate junipers and sagebrush to help grazing, and reduce some dominant plants to increase vegetation diversity. The environmental statement won't discuss timber harvesting, timber roads, and campaigns against noxious weeds.

The agency traditionally has used fire, herbicides, bulldozers and chain saws and biological methods to keep unwanted vegetation in check. Biological agents include cattle and parasitic insects.

"The use of herbicides has been controversial and recently the use of prescribed fires has become an issue in the Intermountain Region," says a "request for help" issued by the Forest Service.

"Your ideas on how plants on the national forest should be managed and what methods are best are important in the decisions we will have to make."

Public comments will be accepted through March, and a draft environmental impact statement should be published in October. Decisions are expected to become final about August, 1990.

Comment should be mailed to Vegetation Management EIS Team, U.S. Forest Service, 324-25th Street, Ogden, UT 84401.