Unseasonably cold weather has turned the time normally reserved for admiring pear blossoms into a tricky minuet with falling temperatures and nesting pests.

Unseasonably cold weather has turned the time normally reserved for admiring pear blossoms into a tricky minuet with falling temperatures and nesting pests.

Rogue Valley orchard crews have battled sub-freezing nights far more than normal this spring. Even if they prevail against persistent winter weather with wind machines and heaters, the usual suspects — spider mites, pear scilla and codling moths — are primed for an attack.

"Cold weather doesn't kill them off," said Philip VanBuskirk, administrator at the Oregon State University-Southern Oregon Research & Extension Center on Hanley Road. "Spider mites are accustomed to waiting for the buds to open to attack. Their eggs are already laid and pear scilla goes out of orchards in the fall when leaves drop and migrate back in at the end of January and the first of February."

While the weekend snow was cause for concern, because of temperature issues and heating fuel costs, local crops fared better than those to the south and north.

"We do have some bud damage," VanBuskirk said. "As we went through orchards at the experiment station, we were seeing a small percentage of blackened or gray buds. But we didn't get hit as hard as some of areas in California where they're not used to getting those kind of freezes. There was major damage to peaches, pears and apples, because they don't have frost protection equipment and generally don't need it."

Medford-based Naumes is a large operator in California's Central Valley, north of Sacramento. President Mike Naumes, was out of the office until today and unavailable for comment.

The Associated Press reported the cold snap has created pollination issues for pear and apple growers in the Hood River Valley.

"We don't think we've had conditions that would result in extensive damage," Oregon State University extension agent Steve Castagnoli told AP. "There are probably some blocks where there was some damage, but it's not valley-wide and it's not a big percentage."

Valley orchardists dodged a bullet, for the most part, over the weekend. VanBuskirk said growers would be happy to see the cold weather move on, but the long-term forecast is for wintry temperatures to linger.

"We're used to an average of 26 nights of orchard protection, mostly with wind machines, during frost season and two to four nights of major heating. We've had quite a few of those nights already," VanBuskirk said. "It would be nice if the snowy weather plain got out of here. The Saturday night snowstorm was scary, because there was no inversion, no warmer air above. If it stayed as cold as they were projecting, it would've caused major damage to the orchards. Wind machines don't do any good where there is no warm air above freezing air. Smudge pots can't maintain heat that long and then you have to start looking at $4 a gallon diesel oil. It can cost thousands of dollars just to heat one night. Potentially you could save the crop, but wouldn't get enough return (on the fruit) to pay for the oil you burned."

Larger operators are less likely to feel the sting of frost because of diversified varieties and locations.

"Bosc and comice blossoms are still not totally open yet, like the D'Anjou and Bartlett are," VanBuskirk said.

So while California growers are assessing their losses and Hood River orchardists are concerned about bees, the Rogue Valley is a comparative bright spot.

"Someone else's problem is our success, as long as we don't get hurt later," he said. "The damage down in California should improve our prices here."

Reach reporter Greg Stiles at 776-4463 or e-mail business@mailtribune.com.