National Potato Crop Outlook
Last month we spoke with growers, this month we asked researchers across the country for their assessment of the 2011 potato crop. Almost all researchers reported crops got off to a late start but generally they are catching up and it should be a good crop, if weather conditions remain stable.
Kent Sather said that San Luis Valley growers experienced a cold and windy spring.
Sather, research associate and manager of the potato certification service at Colorado State University's San Luis Valley Research Center, said that it was one of the windiest springs long-time valley residents could recall.
"No moisture to speak of in the valley," Sather said. "Not a lot of soil moisture from winter precipitation. No real wet snowfall or anything to add to the moisture."
Sather estimates the snowpack in the mountains this year to have been around 80 percent of average.
"Things are looking OK in general," Sather said. "Though growers are saying that their crop is behind by say, one to two weeks. With the size especially, because the temperatures were so cold to start with. Potatoes never really set root and took off like they normally would've, so the size is behind a little bit"
Sather said that the crop could bulk up but the question is can it before the early frosts often arrive in mid-September. His advice for growers is to maintain your fungicide applications for early blight and to "let them mature in a way that makes sense for skin set for storage situations."
Terry Miller of Miller Research in Rupert, Idaho, said that the Idaho crop got off to a slow start because of temperatures but looks good now.
"We have found some early blight," Miller said, "but it's not bad. We've had no late blight, really it's better than we expected, as far as late blight is concerned."
Reports of peach aphids should be of no concern.
"Peach aphids show up usually the end of July," Miller said, "but most growers now have an in-furrow or seed treatment application that takes care of that."
Miller said the summer has been a relatively cool this year without the extreme temperatures Idaho growers normally see in July and the first week of August.
"The crop looks good," Miller said. "The season has been good as far as irrigation and fertility. It looks like we should have a very acceptable crop."
Steve Johnson, crops specialist and Extension professor with the University of Maine, said the season is looking good after getting off to a slow start.
"We started a little late," Johnson said. "We didn't have the most promising spring. We've had some heat and the crop seems to have caught up. We're pretty close to being on schedule."
Johnson said that there has been one case of late blight and that it was limited to one acre that's been killed and hasn't moved. Though there is some late blight in Canada to the east.
"We've had good water, too much water came at once resulting in wash outs, quite localized," Johnson said.
"The crop now looks better than we thought a month ago. It's starting to size up and it may end up better than average with the right weather coming," he said.
Dave Douches, Michigan State University professor in charge of the breeding program, said that the slow start due to a cold, wet spring has put some pressure on the early harvest crop and the recent heat wave through July has put a little stress on the crop.
Douches said that he and Extension agent Chris Long are expecting an "average crop."
"My interpretation right now," Douches said, "is with a little bit of a late planting and the heat coming in July, that maybe it's not as bad as other years because the crop isn't at its bulking stage yet. We're getting a break in the heat right now so I think we're back to more moderate Michigan temperatures."
Douches said that there's been no late blight reported yet. He said that there is some beetle pressure but nothing creating serious economic problems.
One grower told Douches and Long that the solids seem to be okay in the early potatoes despite the heat.
Nina Zidack, director of the Montana Seed Potato Certification Program at Montana State University, said this year's crop is looking very good with most of the crop planted on time.
"Emergence was slow because of the cold, wet weather in May and June," Zidack said. "Since the first of July we've had very favorable growing conditions. Warm days without excessive heat and cool nights."
She said there were no significant disease stresses, no virus pressure and that she was "pleasantly surprised that we're not seeing serious levels of root diseases such as rhizoctonia.
Her pre-harvest advice to growers was to be cautious.
"Be reasonably conservative on your kill dates, not to push things too late in the season. Keeping frost in mind and late season virus transmissions," Zidack said.
Alexander Pavlista, the University of Nebraska Panhandle Research and Extension Center crop physiologist and potato specialist, reports that this year's crop looks good, in general, and should be similar to last year's crop.
"I expect the yields are very much the same as last year," Pavlista said.
It was a cool, wet spring in Nebraska, resulting in delayed planting, he said.
Pavlista said that plants in the panhandle area set their tubers on time and "are bulking very nicely."
"It's time for tubers to bulk and you don't want to hold back on water right now, at least in the panhandle," Pavlista said. "For later season plantings the potatoes are most prone to common scab right now, so it's important to make sure they have sufficient water."
Alan Westra, manager of the seed certification for New York State, said that the season started late across the state because it was so wet.
"Our planting was delayed anywhere from a couple of weeks to a month or more," Westra said.
Seed acreage is down slightly, but not substantially, reported Westra.
"They (seed growers) made adjustments and got caught up on planting and I think our acreages didn't suffer because of the wet weather," he said.
"The only stress we're seeing right now is on the dry-land potatoes," Westra said, "because after the wet spring we've been really dry and hot. Which is the worst combination because if they're wet when they start out they don't develop the root system that they need and when the water turns off, they get cooked."
Don Halseth, Cornell University horticulturist,said he was very pessimistic about this year's crop due to the dry conditions until this weekend's rainfall on Aug. 6-7 gave him cause for re-evaluation.
"We got a million dollar rain this weekend and that was very timely," Halseth said. "I'm hoping the rest of the state got it."
He said that the wet spring delayed plantings, creating stand establishment problems that were exacerbated by lack of rainfall in June and July.
"Visiting fields the last two weeks it was apparent we needed rainfall and we got an inch and a half, inch and three-quarters this weekend," Halseth said. "Greatly improved the prospects for reasonable yields. Still need a good rain or two between now and the first of September."
"Pretty phenomenal and actually an amazing weather system this year. It's unprecedented," said Phil Hamm, plant pathologist and superintendent of Oregon State University's Hermiston Agricultural Research and Extension Center.
"We've had extremely good potato growing weather. Our concern was for the early, big harvested potatoes, started just after July 4. Because our heat units were so reduced we expected yields to be off but actually the yields were very good for early potatoes."
Hamm said that there's been no sign of late blight or early blight. No insect issues to speak off, the cool weather has kept their impact to a minimum.
Hamm advised growers to be "mindful of late blight, still advising weekly applications of protective fungicides for late blight. Be watchful for controlling aphids, Colorado potato beetle and beet leafhoppers."
"Conditions for growing have been exceptional," he said.
Red River Valley
Willem Schrage reports that the Red River Valley is late due to a late spring with lots of moisture but that most fields have recovered and are looking pretty good.
"We've had quite a bit of heat the last few weeks," said Schrage, director of the North Dakota State Seed Department.
"In general it looks like we have a pretty good crop," he said. "I think most people will get a good crop with a few exceptions."
His advice to Red River Valley growers was to keep up with the spray schedule.
Washington growers have seen some late blight north of Pasco up to Basin City and a little northeast of Burbank, said Dennis Johnson, Washington State University plant pathologist.
"They are managing it very well," he said.
Johnson attributed the late blight to a shortage of seed this year resulting in some growers using infected seed.
"We were slow coming out of the ground here in the Columbia Basin but we make up for it with heat units later in the year," Johnson said.
Johnson advises growers to pay attention to detail on watering.
"Water needs will be going down in August," Johnson said. "They should pull off their water a little bit."
Johnson also said that growers should review Chapter 9 "Potato Health from Sprouting to Harvest," by Neil Gudmestad from the second edition of Potato Health Management.
Johnson advises growers to avoid harvesting in rainy weather.
"There will be late blight spores in the air," Johnson said. "If it's wet they get washed out of the atmosphere and land down on the tubers and the tubers are inoculated going into storage and there'll be a rot problem."
According to Amanda Gevens, University of Wisconsin-Madison plant pathologist: "We've had very warm temperatures with a good balance of showers. Sporadic storms in the Central Sands area did challenge some fields in mid-July. Decent enough rainfall, not experiencing drought conditions at this time."
"Disease pressure is relatively low," Gevens said. "Early blight is the most commonly seen disease in Wisconsin. We just don't have much of it yet this year."
"Early dying can be seen in some plantings," she said. "Blackleaf has been noted throughout the state in low incidence."
"Growers are on high alert for late blight," she said.
There has been just one report of late blight, in Waukesha County on tomato, but that appears to have been an isolated incident with no additional reports since early July."
She did advise growers to continue to be watchful for late blight.
"Overall the crop looks very good this year," Gevens said. "Mid- and late plantings should provide good harvests. With early plantings, we had some seed decay due to a cool, prolonged spring."