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These trees love sewage Photo by Steve Johnson Richard Roseburg, an Oregon State University Extension Service scientist, walks amid a grove of hybrid poplar trees being used as a test plot at the Extension Service's station west of Medford. The trees have earned a reputation for being able to use water no one else wants -- such as effluent from a sewage plant -- and growing quickly into a high-fiber source. Poplar trees could prove very popular Hybrids could be used to absorb sewer outflow and produce jobs By PAUL FATTIG CENTRAL POINT -- When Richard Roseburg walks among the poplar grove at the Southern Oregon Research and Extension Center, he sees more than healthy trees. The Oregon State University soil scientist sees potential solutions to vexing problems facing the growing Rogue Valley population. The fast-growing hybrid trees could be used to absorb sewer outflow while producing jobs and fiber, he says. "The sewage treatment plant is looking for a better way to discharge its effluent," he said of Medford's regional water reclamation facility. "Agricultural areas like Sams Valley would really benefit if more water was available. "If they could produce a fiber crop using treated effluent, it could be used by the local fiber-based industry we already have in place here," he added. The hybrid poplar grove covering one-and-a-half acres is a control group being studied along with a smaller grove at Medford's sewage plant along Kirtland Road. The plant treats the sewage for nearly all communities in Jackson County except Ashland. Roseburg will discuss the potential of hybrid poplars at during a public tour of the grove at 7 p.m. Thursday at the research center, 569 Hanley Road. Although the tour is open to all, small woodland owners and farmers are particularly encouraged to attend. The seedlings at the research center were planted in April 1997. Originally no larger than a pencil, the larger ones have thrived in the rich soil. The largest are now roughly 6 inches in diameter and stand some 38 feet tall. The grove at the treatment plant was planted in the extremely poor, rocky soil along Kirtland Road in 1996. Although they are smaller than their Hanley Road counterparts, the Kirtland Road trees are also doing well, thanks to the treated effluent, Roseburg said. No effluent is being piped to the research center plot along Hanley Road. The research began when the city of Medford began looking for an economically and environmentally sound way to discharge its effluent, Roseburg said, noting that Medford has to dispose of 10,000 acre-feet of treated effluent each summer. The treated effluent is now released into the Rogue River. While effluent can't be used to directly irrigate food crops, it can be used with some restrictions on forage crops and with virtually no restrictions on fiber crops, Roseburg said. Using the treated effluent for such crops would also reduce pressure for stream habitat and recreation, he noted. "That's really the basis for doing the research at the treatment plant," he said. "We're carefully monitoring the ground water, the root zone water and the water use. "Here (Hanley Road site), I'm looking at what kind of growth rate and production we can expect in good soil," he added. "The soil at the treatment plant has got to be some of the worst agricultural soil in the state." He estimates the soil is at least 50 percent rocks. "But, even given that horrible soil, it's been a success," he said. "The production of those trees is much higher than forage grasses growing out there. The trees' vigor is allowing them to grow, even under difficult conditions." There are commercial hybrid poplar plantations already growing in the Pacific Northwest, he noted. "These trees need a lot of water and a lot of nutrients," he said. "You have the water available and you have nutrients in the effluent already. "We're hoping to get a couple of more years of data here," he added. "But it's already showing a lot of potential." Mail Tribune Copyright � The Mail Tribune 1999, Medford, Oregon USA