The seven-foot-high wall of muddy water came down the creek bed like a freight train and caught the rancher by surprise.

The July 1991 thunderstorm had dumped about 1 inch of rain in 30 minutes in the Newsom Creek drainage near Post, and the rancher was trying to move several horses away from the rising creek.

But the flood waters washed away a D-7 Caterpillar tractor and barn and caught the rancher. He was swept about a mile downstream and drowned.

”A flash flood is not unusual for the area,” said Tim Debodt, Crook County extension agent, ”but junipers in that watershed created a condition where there was nothing to slow down the water.”

Since that tragedy, an active juniper management program has begun in the Newsom Creek area, Debodt said. Some of the trees have been removed or thinned, and native grasses have been re-established to help soak up runoff.

Junipers are native to the High Desert. But before European settlers arrived in the area, Debodt said, junipers were controlled by fires that swept the desert every 15 to 30 years.

But grazing and fire suppression changed that, he said, and now a controversy has developed about how to control the steadily increasing juniper population.

On one side are those who believe partial or complete removal of the trees is the best way to restore a balance in the High Desert ecosystem.

On the other are people who say junipers are a natural part of the ecosystem, and that the trees are being blamed for problems that originated elsewhere.

People on both sides ”are really impassioned about junipers,” said Gilly Lyons of the Oregon Natural Desert Association. ”Is juniper encroachment a problem in Central Oregon? It depends on how you define a ‘problem.’ This is not the catastrophe some people think it is.”

About 5 percent of Eastern Oregon is affected, or has the potential to be affected, by juniper encroachment, Lyons said. Another study, completed in 1988 by David Azuma and other foresters of the Pacific Northwest Research Station, estimates junipers occupy 2.2 million acres in Oregon.

But it’s the location of those junipers that concerns state and federal agencies.

”In some places, such as in the higher elevations of the Steens Mountains, Hart Mountain and around the John Day area, junipers are seriously hurting wildlife habitat,” said Tony Svejcar of the Department of Agriculture’s research service in Burns. ”When you have between 20 to 30 junipers per acre, those areas remain healthy. But when an area gets 100 to 300 trees, they’ll take over the site.”

This proliferation can degrade habitat to the point where many native species are forced to relocate, said Glen Ardt, a biologist with the Oregon Department of Fish and Wildlife (ODFW).

ODFW tests show 146 species live in the natural, shrub and bunch grass high desert, he said. But in areas where there is a moderate spread of junipers, he added, this number drops to between 100 to 125, and old growth stands will only support about 81 species.

”Some species, such as birds, may eat the berries and nest in the branches,” Ardt said. ”The trees can provide cover for deer and elk, and initially, the young junipers won’t out-compete the grasses for moisture and light.”

But the trees are long-living and spread easily, and they suck the moisture out of the already arid desert soil, Svejcar said, which in turn causes native sagebrush, bitterbrush and bunch grasses to die out.

The crowns of junipers can intercept nearly half of the precipitation falling on them, according to another study, and return it to the atmosphere through evaporation and sublimation.

This drain of moisture drastically alters or destroys wildlife habitat and creates areas where nothing else can grow, Svejcar said. Then, when the infrequent rains come, the fragile topsoil is eroded.

Another aspect of the problem, said Clint Jacks of the Oregon State University Extension Service is that junipers use available soil moisture very early in the spring before other plants begin to grow.

”New juniper woodlands pose a critical threat to watershed and ecosystem health,” Jacks said.

However, Tim Lillebo of the Oregon Natural Resources Council disagrees. The expansion of junipers into former grassland areas is part of a natural cycle, he said.

”Junipers have been east of the Cascades for thousands of years,” Lillebo said. ”Pollen counts in lake sediments show the junipers’ range has expanded and contracted regularly.”

Overgrazing, Lyons said, led to the spread of junipers in some areas.

”The high desert area never had large herds of buffalo, or other grazing animals. There wasn’t any grazing here until the settlers brought in cattle and sheep,” Lyons said. ”This ecosystem never evolved in the presence of grazing pressure.”

Ardt said juniper control is costly and difficult and right now there is no easy fix for the problem areas.

The ideal situation would be to have a ”mosaic of native trees, shrubs and grasses,” where junipers would not be the dominant plant, he said.

But in some areas, that would require massive removal of adult trees, and that is not economically feasible.

”There is a small market for juniper wood, but not enough to make logging a profitable option,” Ardt said.

The Oregon Natural Desert Association supports control methods that are ”ecologically friendly,” Lyons said. These techniques could include burning specific trees in certain areas, doing controlled burns and cutting down some of the junipers and spreading the branches on the ground to decay so the nitrogen present in the trimmings could return to the soil.

”Most of these methods are site-specific,” Lyons said. ”There is no overall best approach.”

At some point, Jacks said, fire will have to be reintroduced into the ecosystem.

”Since fire once helped develop the ecosystem,” he said, ”it can still play a beneficial role as a maintenance tool.”