Summary: Jury isn't still out: Roads, clearcuts cause majority of landslides

Writers in the last century would not be surprised by the fact that eight people died in Oregon in November in landslide-related accidents or that five of those deaths involved landslides starting in logged areas or clear-cuts. Many books, including "Man and Nature," by George Perkins Marsh, 1862, detail the relationship between logging and both floods and landslides.

In the Coast Range alone, there are hundreds and hundreds of recent landslides, most of which originate at logging roads or in logged areas. There is an enormous amount of property damage: thousands of tons of sediment in streams, families left without homes and major damage to fisheries.

No rational witness of the destruction can debate the relationship between logging and landslides.

But what the Oregon Department of Forestry says following these tragedies is: (1) that "the jury is still out" regarding logging and landslides, and (2) that whether it is out or in, public safety is not its responsibility.

Huh?

The simple truth is that there is abundant and overwhelming evidence that clear-cutting and logging roads cause huge increases in landslides and flooding. The jury is not out. The jury is in, and the verdict is guilty.

Look at the science regarding landslides:

1971. R.L. Fredrickson, in a U.S. Department of Agriculture Forest Service Pacific Northwest research paper, reported that the greatest soil loss in the 1964 storm was from mudflows and landslides, and these were more frequent at roads and at clear-cuts.

1977, R.R. Ziemer and D.N. Swanston, in a USDA Forest Service research note, said: "A crucial factor in the stability of steep forested slopes is the role of plant roots in maintaining the shear strength of soil mantles. . . . Once the covering vegetation is removed, these roots deteriorate and much of the soil strength is lost."

1981, Masters of Science thesis, Daniel A. Marion, Oregon State University, geology: "Clear-cutting and road construction appears to strongly affect landslide frequency and location. Landslides occur 24 and 253 times more frequently (relative to forest rate) in clear-cuts and road areas, respectively."

1986, M.S. thesis, Margaret McHugh, OSU, geology: "(H)arvested areas showed an increase in failure rate of 7 times and roaded areas an increase of 48 times that of forested terrain."

Regarding floods:

1979 in a USDA Forest Service research paper, R. Harr, R. Dennis and R. L. Fredrickson report: "In . . . western Oregon, two such studies have shown that clear-cut logging of entire small watersheds in . . . the Coast and western Cascades Ranges can cause absolute increases in annual water runoff yield that are among the largest in the world." Over a 5-year period, they found that annual runoff increased 43 percent in clear-cuts, 14 percent in small clear-cuts, and 8 percent in shelterwood cuts. The also found that peak flow increased 48 percent in clear-cuts, 35 percent in small clear-cuts and 11 percent in shelterwood cuts.

Research like that is why the Oregon Department of Forestry itself, in its 1995 publication "Cumulative Effects of Forest Practices in Oregon," states, "Timber harvest in sensitive areas has also been associated with increased incidence of mass movement. Clear-cut harvest and/or slash burning on steep slopes may increase failure rates two to 40 times over rates on undisturbed sites."

But that is not what they are saying in 1996. Now they are saying that "the jury is out" on the relationship between logging and landslides.

Hogwash. They should be ashamed. The Oregon Department of Forestry, incredibly enough, refuses to tell us the truth even when they are the author of that truth!

The Oregon State Forest Practices Act doesn't require forestry department personnel to warn folks whose homes are likely to be trashed because of logging and it doesn't authorize the department to stop the logging.

But simple decency would dictate that it should have. Landslides can kill. The department says that public safety is not its job. It should be.

The law must be changed, strengthened and enforced by folks who are not industry apologists. We all must insure that those changes take place.

It is clear that the Oregon Department of Forestry has a policy of concealing all risks -- to people, property, fish, wildlife and other resources -- which result from logging. That's intolerable.

We don't need cheerleaders for industrial logging. Instead we need the opposite: protectors of the products and contents of watersheds -- pure clear water, fish, wildlife, public roads and bridges and families' homes and human lives.

We must start over with a new agency -- one devoted to forestry, not deforestry.

Tom Giesen of Eugene wrote this on on behalf of The New Alliance for the Forest and The Native Forest Council.