After months of battling highway officials over where trees can be planted along roadways, Arlington County will finally get the "urban boulevard" effect it wants on Rte. 1 when the road is widened through Crystal City.

Rep. Frank R. Wolf (R-Va.) has successfully appealed to the Federal Highway Administration headquarters in Washington to overrule its Richmond field office's edict prohibiting Arlington from planting trees curbside.

The county wants to create a shaded, boulevard effect along the 1.8 miles of the congested road scheduled for a $37 million widening this year. The county finally got the state highway department to agree to the plan, but the Richmond office said it wanted all street trees a minimum of nine feet from the curb to "protect" motorists.

Highway engineers have said that roadways need "clear zones" because curbside trees can present distractions to motorists and leave little leeway for avoiding a collision if a car skids off the road.

Wolf said he got involved in the issue after Henry S. Hulme Jr., the county's transportation chief, asked for help. Hulme said the FHA's Richmond office had indicated it would disapprove the road's design plan, thus holding up the long-awaited project, unless the trees were placed back.

Noting that there would be six-inch curbs and a relatively slow speed limit of 35 mph, Hulme wrote Wolf, "It does not seem reasonable to 'protect' the motorist from street trees when pedestrians are walking in the same area, and at the same time utility poles and light standards are also allowed to be there."

Wolf said FHA Deputy Administrator L.P. Lamm agreed.