Marijuana production on federal lands managed by the Bureau of Land Management in Idaho rose an unexpected 5 percent in 1994, and officials believe that reflects the state's dramatic population growth.

Law enforcement officials seized a total of 523 marijuana plants on BLM land this year compared to 500 a year ago. All the 1994 seizures were in Owyhee and Jerome counties.Dan Hughes, the bureau's top enforcement agent in Idaho, had expected a decline in production this year because of the drought.

"Marijuana plants take quite a bit of water to grow so with the drought conditions in 1994, we though growers would be less likely to spend the considerable amount of time and energy it takes to plant seeds and get water to them in a dry year," Hughes said.

The vast, remote tracts of public lands throughout the state, Hughes said, are very alluring to marijuana growers and the manufacturers of other drugs particularly methamphetamines.

"A grower would much prefer to go onto a public land site than a private land site that might be monitored a little more closely," he said. "They feel secure in very remote areas, and probably the biggest motivation is just remoteness."

But drug operations on public lands pose major threats to both recreationists and the environment.

Hughes said marijuana growers have been known to take drastic steps to protect their crops including booby traps, vicious dogs and firearms. He recommends recreationists stumbling into a marijuana garden retrace their steps and get out as quickly as possible. Then they should notify authorities, he said.

Environmentally, Hughes said cultivation can create serious erosion problems in fragile soils while the chemicals used by growers can be detrimental fish or wildlife.