OREGON STATE UNIVERSITY

Poplar tree farming low, not no, maintenance

09/12/1997

ONTARIO - Hybrid poplar tree plantations are popping up around Oregon faster than espresso stands and part of the attraction is the apparent ease in growing them.

People figure you plunge an eight-inch stick in the ground in the spring and come back eight to12 years later to a forest ready to harvest for pulp wood or saw boards.

It's not quite that easy, Oregon State University experts say.

OSU researcher Erik Feibert points to some nine-foot poplars in irrigation test plots at the university's Malheur Experiment Station here. They were, indeed, just eight-inch sticks when they went in the ground in April.

"Pretty amazing," said Feibert, "but they do take a lot of water and care early on."

He then points to the weed patch a little further down the hill that is the "check" plot in a weed control study.

"We planted the same kind of poplars there at the same time and haven't done anything to them since," Feibert said. "As you can see, the weeds are taller than the poplars."

Somewhere between doing nothing, and what looks like manicured orchard care, describes the rest of the popular tree test plots.

Feibert is testing a wide range of irrigation treatments.

"We don't really know all the exact costs of production and payoffs yet because there is such a long gap between planting and harvest," he said. "These plots should give us some answers.

"This year we're experimenting with growing crops and ground covers between the rows. Of course you can only do this for the first couple years until the trees get so tall they shade out any possible between-tree growth," he added. "Squash, alfalfa and wheat are all crops that could help poplar growers supplement their income during the first two years of tree growth."

Marilyn Moore, an agent in the OSU Extension Service's Malheur County office, notes that managing water and weed control have been the big challenges for growers in Malheur County.

Typical irrigation for popular plantations is 24 inches of water a year, with one-quarter of the water applied from April through July, one-half when the trees are growing fastest (July and August), and the remainder from the end of August through September.

In addition to watering and weed control, a person growing poplars for saw boards needs to prune the trees in the winter of the second and third years, Moore said. This reduces the numbers of knots, making the wood more valuable for boards.

"We think we can grow 18-inch saw logs in eight to 10 years with possible yields of $25,000 (worth of) board feet per acre," Moore said. "According to current estimates, this adds up to a return of about $1,500 per acre per year. We have about 300 acres in plantation plots now, but we're hoping to add 300 acres each year.

"There hasn't been a large market for poplar lumber in the U.S., but it is quite common Europe and Japan," said Moore. "Though it seems like a soft wood, when kiln-dried, poplar is strong and prized for its white color.

"Since timber supplies are tight, wood processors are starting to show interest," she added. "We're getting many inquiries about the number of acres we have planted and how soon the wood will be available."

She points out that poplar farming is supported the Oregon Lottery's regional strategies program. This comes in the form of technical support for growers and funds for research and marketing. Raising poplar provides another agricultural option for areas in eastern Oregon such as Wallowa, Union, Malheur and Baker counties.

Oregonians are growing hybrid cottonwood trees in a similar manner in many other parts of the state, such as along the Columbia River, says Moore, but that wood will be used for pulp. The economics of paper production requires that trees be within 100 miles of a pulp and paper mill, she noted.