Wednesday, May 4, 2011
While last week's early morning frost may not have been particularly unusual, orchardists in the valley are still scouting for the damaging effects of this growing season's cold on burgeoning tree fruit buds.
"Any damage we are seeing out there is more likely due to the two extreme cold events we had in November and February," said Steve Castagnoli, horticulture agent for the OSU Extension office in Hood River.
Castagnoli is referring to this year's elongated cold season in which the valley saw unusually early drops into single-digit temperatures during late November and unusually late cold temperatures hovering around zero through February.
Although not always the best predictor of future flower-to-fruit-set success, some farmers are taking tree cuttings and "forcing" blooms early to evaluate the condition of buds.
"If you walk through some orchards right now you can see that some of the buds are not developing normally," said Castagnoli. "There is no way to reverse damage - but farmers can adjust farming practices to adapt to the information."
"In some blocks, you can touch the buds and they are just dead; just breaking off," said Gordy Sato of Ray Sato Orchards in Parkdale.
"We're sure the damage here was done in November with the cold, when the trees were not dormant yet," he added. "Of course, minus-4 degrees in February didn't help."
Meanwhile, Mother Nature is resilient.
"You only need 10 to 30 percent of the buds to set fruit in order to have a full crop," said Castagnoli. "We can say we have damage, but it is hard to predict what the end result will be from that."
Even after a successful bud-to-bloom period, orchards go through a process of natural thinning, in which both blooms and fruit-lets die off.
"We always try to manipulate Mother Nature, but she always does what she wants anyway," said WSU Extension Educator Gwen Hoheisel, speaking on behalf of Yakima-area orchardists, who often compete with Hood River Valley producers for crop sales.
"We saw the same early and late cold events that Hood River did," said Hoheisel. "Our grapes were very affected but the apples and pears seem largely safe. There is some browning at the base of our buds but blooms are still pushing through."
Hood River, like Yakima, also contains extremely diverse microclimates in which a single mile traveled between farms can spell the difference between a total crop loss due to weather and a completely normal harvest.
"All any orchardist needs is just enough flowers to get through pollination and fruit set," said Hoheisel. But, you also need bees that are willing and able to work to make that pollination happen.
"The bees will only come out if it's not cold or windy or rainy," said Sato. "The lower valley had blossoms out and two warm days this last weekend, so they've got good pollination started."
Unfortunately rain, cold and wind are predicted for the remainder of this week, including occasional bouts of sleet.
Parkdale blossoms are still in the fingerling stage - a "tricky time," according to Sato. "We've got our fingers crossed."