By RAELYNN RICARTE
News staff writer
August 9, 2006
Horticulturalist Janet Turner faces a daunting task — she is training hundreds of pear trees how to grow on a trellis at the Mid-Columbia Agriculture Research and Extension Center.
“I do talk to the trees a lot. But as long as they don’t answer I’m fine,” she said on Tuesday’s walk through the Competitive Orchard Systems 2015 plot.
In two years, Turner wants the 770 trees on the .85-acre experimental site ready for harvest. She is hopeful that laborers will be able to put away ladders and use a picking machine that can harvest from five to seven rows at a time.
Turner and Clark Seavert, superintendent of the research facilities operated by Oregon State University believe that a fruiting wall, as opposed to the sweeping canopy of a traditional tree, will provide farmers with at least a 15 percent return on their investment.
Turner said the challenge to creating a uniform wall of pears is that there is no dwarf root stock available at this time. She said apple trees have been easily converted into a hedge row because of the root stock options. Turner said cherry trees have also been difficult to control for a fruiting wall because of their vigorous growth.
A root stock is the “brain” that signals the tree about how big the fruit should be and influences other characteristics. Turner believes that a dwarf match for cherries and pears will eventually be cultivated.
“It’s just a matter of time. We’re starting a little late with this search. But the Hood River Valley is all about pears so it’s time to start focusing on what we need,” she said.
Ideally, said Turner, the trees pruned to be more like a cross between a shrub and a vine will be less costly to maintain. In addition to the convenience of harvest, she said water and fertilizer applications should be more efficient, and fewer chemicals are needed to control pests and disease.
Both Turner and Seavert also expect the hedge rows to yield mostly top grade fruit since the wind will not buffet branches. And lower limbs will not be shadowed by an umbrella of leaves.
“I’m basically making windows of opportunity for sunlight to come through,” said Turner. “The goal is to build a structure for the best quality of fruit.”
She acknowledges there is a long way to go before COS root stock is ready for delivery to local orchardists. Turner is still trying to figure out how to get branches no more than three inches above and one inch below the wires spaced 18 inches apart. She routinely walks through the rows snapping off competitors and tying suitable limbs in place. When there are no choices available, Turner will try scoring the trunk just above a branch to stop the flow of hormones that inhibit growth and encourage a new sprout.
Adding to the pressure of her job is the fact the trees are being encouraged to sprout six inches per week during the 16 weeks of the peak growing season.
“This is a little more intensive than we’re used to,” said Turner.
She said the norm is for the top of a pear tree to get 18 inches of new growth during the season. She will strive to hold each tree at 10 feet tall and four feet wide — with fruit production beginning in the third year.
“You want things on a very linear and very orderly basis to create a two-dimensional form,” she said.
Turner is also studying how long it takes a bud stick that has been bench-grafted onto one of 428 different selections of Horner pear root stocks to develop a canopy. She wants to know if the engineered trees, which are cheaper to plant, can compete with a finished tree in fruition.
And then there is the study involved in placing aisles of trees closer together, and whether the fruiting wall works better for Bartlett, Bosc, Comice or Anjou varieties.
Turner even has a test variety from West Virginia thrown into the mix. The new pear stays fresher in cold storage and seems more resistant to fire blight, a destructive bacterial disease.
She said an OSU survey of 1,700 consumers determined the East Coast pear had a good taste and texture. And, since it is fairly small, Turner said that bodes well for a root stock that is adaptable to a fruiting wall.
“If it passes all the tests, we want to name it for the region. It could be used to fill the gap in other varieties and compete against southern hemisphere fruits,” she said.
With farming production costs rising three to four percent a year, Turner said the research center is continually looking for ways to it make the industry more profitable.