On a farmer's field in west Eugene, Spectra-Physics Inc. is using the latest in technology to speed the creation of wetland forests and grasslands that originally took mother nature centuries to produce.

If the experiment works, the result by winter 1991 will be an infant wetlands park along the Amazon Channel with more than 10,000 young trees and shrubs thriving in their new watery environs.

Before that happens, however, crews of excavators, earthmovers, seed sowers and tree planters will have been called upon to transform fields that were used for agricultural purposes for more than 50 years.

"I hate to use the word cutting edge, but that's what it really is," Portland ecologist Paul Fishman said of the techniques being used to establish 32 acres of wetlands on the 40-acre site. Fishman is among a team of consultants hired to advise Spectra-Physics on the project.

Expected to cost at least $775,000, the project stands out as one of the few wetlands replacement projects carried out in the Eugene-Springfield area.

"Certainly, it's the first of this magnitude or of this complexity," said Steve Gordon, a wetlands expert for the Lane Council of Governments.

Spectra-Physics is creating the wetlands under orders from the U.S. Environmental Protection Agency and U.S. Army Corps of Engineers, which regulate the conditions under which the nation's dwindling wetlands may be filled. The Bush administration has set a goal of no net loss of wetlands.

Now under construction on a site a short distance northwest of the Spectra-Physics site on Terry Street, some of the new wetlands are being created to make amends for 12 acres of wetlands that were filled when the high-tech firm built its west Eugene plant in the early 1980s.

The company, which manufactures optical scanners to read the bar codes on merchandise, didn't know at the time thatthere were wetlands on the site.

The remaining wetlands are being created so the company can proceed with plans for an $8 million expansion that will entail filling another seven acres of wetlands on the same site. An ash forest, which ranks as a top-quality wetland, will be preserved.

Spectra-Physics has received the necessary fill permits from the Corps of Engineers and Oregon Division of State Lands, Facilities Manager Charles Missar said. No date has been set for the ground breaking.

"We are still developing the plans for what we're going to be doing," Missar said. Company officials plan to hold a strategy session in the next few weeks to resolve issues surrounding expansion of the plant, he said.

"Business continues to be very good, and we are still growing," he said, "but the growth is going to be evolutionary, not revolutionary."

Some of the wetlands that originally were filled on the Spectra-Physics site were forests that rank among the most highly valued types of wetlands. As a result, the EPA is requiring the new site to include an interwoven mix of forested and prairie wetlands along with the creation of new uplands as a protective buffer.

Fishman, the wetlands consultant, said the resulting willow and ash groves should more closely resemble traditional Willamette Valley wetlands than some recent mitigation projects he's seen with ponds, islands for ducks to nest on and some wetlands plants around the edges.

Early work on the Spectra-Physics project, which began last winter, has gone well, Missar said.

"We feel fairly confident that most of the things that we've done will work, based on experiences in other places and some of the trial plantings that we've done," he said.

Work began last winter with the transplanting of about 100 ash seedlings from other west Eugene locations to make sure they could survive in their new home. Nearly a year later, 80 percent to 90 percent of the trees are doing fine, Fishman said.

Late last summer, crews from Delta Sand & Gravel & Construction Co. began excavating portions of the site to reduce the elevation to groundwater level.

The site already is crisscrossed by the Amazon Channel, Amazon Creek and a drainage ditch, so reintroducing water to the fields only required adding some channels, Missar said.

"Wetland plants generally like to have their feet wet during the winter," he said.

The tricky part was still ahead: figuring out a way to bring back the diverse plant species that grow naturally on wet prairies, which used to cover west Eugene before non-Indian settlers arrived in the mid-1800s and began draining the area for farming.

Delta Sand and Gravel came up with one solution. Using 4-foot by 8-foot metal plates specially made for the project, crews placed the forms across an acre of wetlands at the current Spectra-Physics site.

They used chain saws to cut around the edges, then loaded the sod mats onto a flatbed trailer and drove them to the new site, where they were unloaded onto an excavated field.

Fishman, who was laying stakes at the site one sunny afternoon last week, eyed the mats of wetland soil a bit nervously. "I'm kind of doing a little rain dance here," he said.

A Junction City grass seed farmer helped Spectra-Physics find a local source of seeds for tufted hair grass, a species native to prairie wetlands but considered a weed by farmers.

After obtaining the permission of some surprised property owners, the grass seed farmer harvested thick stands of the tall grass, then threshed and cleaned the seeds, which will be planted in the next couple of weeks, Fishman said.

Other seeds native to the area were gathered by running a "big lawn vacuum" across abandoned agricultural fields near the mitigation site that already were reverting to wetlands, he said. Fishman said owners of the fields were equally perplexed, asking him, "You want to do what?"

The planting of trees and shrubs is being timed to coincide with the beginning of the rainy season. Included this fall and winter will be more than 1,000 additional ash seedlings along with cottonwood and willow trees, and hawthorne and wild rose bushes. Planting will continue through next winter.

The biggest challenge, Fishman said, will be giving the tufted hair grass a chance to grow by wiping out a "tremendous reserve of seeds" left by earlier ryegrass crops and reed canary grass that grew wild.

The unanimous verdict among agricultural experts is that only a combination of burning, plowing and limited applications of herbicides will be successful, he said. Regarding the need to resort to herbicides, he said, "I even hate to say that. We'll use as little as we can."

Monitoring of the wetlands will continue long after the last planting. The EPA expects the wetlands to be checked periodically for five years to make sure the new plants are growing well and attracting waterfowl and other wildlife.

Missar said Spectra-Physics still envisions turning the completed wetlands over to the city as an environmental park. "We are still negotiating on that, but that's what we'd like to have happen," he said.

The city is interested in making the site the beginning of a potential wetlands recreational corridor stretching along the Amazon Channel.

Final details of financing for the public-private project still are being worked out, but the city has agreed to pay $217,000 and the state about $250,000, said Jim Croteau of the Eugene Planning Division. Spectra-Physics expects to pay an amount equal to the combined city-state contribution, Missar said.

Like Missar, Fishman said he is reasonably confident that the experiment in creating prairie and forested wetlands will prove successful, but he acknowledges that such projects are risky.

"It's really a pretty new science," he said. "It's more of an art at this point, I think."