Growing a successful seed potato crop means navigating two major variables: weather and disease/pest pressure. For the most part, growers were able to clear these hurdles in the 2018 season.
Growers nationwide didn’t experience anything apart from the ordinary cycles of warm/cool and wet/dry but there were a few exceptions. Andrew Houser, manager of the Colorado Potato Certification Service, said weather conditions in the San Luis Valley were “very unique.”
“In typical years, winter temperatures can drop to 20 or 30 below zero. This past winter, temperatures rarely dropped below zero. This was in large part due to lack of snowpack in the surrounding mountain ranges. The warm temperatures continued through May and June, resulting in a fast growing potato crop,” Houser said.
Idaho growers reported a tough planting season due to heavy rains, while in Michigan excess moisture bogged down the harvest.
In general, growers were able to dodge severe problems with the usual roster of threats, including PVY, dickeye, blackleg, Colorado potato beetle and others.
State Seed Report Roundup 2018: Western United States
RELATED: Seed Report for Eastern, Central U.S.
Colorado
Seed inspections started a week earlier (June 19) this year. Certified seed growers began killing vines in late July and early August, limiting potential spread of virus by aphids. At the end of October, most of the potato acreage was harvested in Colorado. Overall yields and sizing have been above average, due in part to the warm weather this summer.
Certified seed growers are in the process of submitting seed lot samples for the postharvest test, which takes place at the North Shore of Oahu, Hawaii. A postharvest test is required on all certified seed in Colorado, whether it is sold commercially or for recertification. An official 2018 certified seed directory is posted online at http://potatoes.colostate.edu/potato-certification-service/. An interactive version of the same certified seed directory is part of the Colorado Certified Potato Growers’ Association website at www.coloradocertifiedpotatogrowers.com.
In 2018, Colorado certified seed potato acreage was up overall from 10,093 acres in 2017 to 10,282 acres in 2018 (1,469 of these acres qualify for grower plant back only). The total accepted certified acreage after summer field inspections was 9,306 acres. Rejections were primarily the result of PVY/mosaic, with a few rejections caused by blackleg and variety mix. Total potato acreage (both certified and commercial) in the San Luis Valley was 51,785 acres, up from 51,648 acres in 2017.
The 2018 top five certified potato varieties in Colorado are:
- Russet Norkotah selections (2,495 acres)
- Canela Russet (853 acres)
- Centennial Russet (632 acres)
- Teton Russet (562 acres)
- Lamoka (507 acres)
A wide range of potato varieties are also certified in Colorado including multiple varieties of russets, reds, yellows, chippers, fingerlings and specialties.
The Colorado Seed Act requires all seed lots imported into Colorado to undergo a postharvest test or winter grow-out. Also, a PVYN tolerance of 1.0 percent is in place for all seed coming into Colorado. If you are a seed grower intending to ship seed into Colorado, contact your certifying agency for submitting samples for postharvest testing. Also, there is a late-blight quarantine in effect for all seed coming into the San Luis Valley. If you are planning on shipping any seed into the valley, this test needs to be conducted by a qualified lab prior to shipment. Check our website for testing specifics: http://potatoes.colostate.edu/wp-content/uploads/2014/02/Late-Blight-Quar-2014.pdf.
— Andrew Houser, manager, Colorado Potato Certification Service.
Idaho
As this article is being written (Oct. 4), harvest of the 2018 Idaho seed potato crop is winding down. Many Idaho seed growers had a difficult planting season with significant delays due to rain. As a result, yield reports are mixed with some growers are reporting average to good yields, while others are reporting lower than average yields. Quality going into storage is reported as good to excellent.
Overall, the 2018 crop had a higher set than normal and appears to have a very nice size profile. Seed health appears to be steady from 2017. The number of seed lots with visually detectable levels of PVY decreased slightly compared to last year. There were no BRR detections during field inspections.
Seed availability is predicted to impact not only by an overall lower to average yield, but also by a significant reduction in certified seed acreage. At the conclusion of the second round of field inspections, a total of 29,295 acres are eligible for final certification this year. This is down approximately 10 percent from 2017. Excluding proprietary genetics, the 2018 acreage accepted for certification represents a total of 149 varieties, selections, and advanced clones.
For 2018, the top varieties were Russet Burbank (41 percent of total acreage accepted), Russet Norkotah (all strains, 18 percent of total), Ranger Russet (12 percent), Clearwater Russet (4 percent), Alturas (3 percent) and Umatilla Russet (3 percent). Seed acreage of Russet Burbank, Russet Norkotah, and Alturas is off approximately 7 percent compared to 2017. Clearwater Russet acreage increased slightly (+3 percent), while there was a 15 percent reduction in Umatilla Russet acreage compared to 2017. A complete listing of this year’s seed potato crop is available in the 2018 Idaho Certified Seed Potato Directory, posted on the Idaho Crop Improvement website at www.idahocrop.com.
Idaho growers have proposed a change to the nomenclature used to describe seed potato generations. In place of the current system, it is proposed that Idaho seed generations will be designated by field year. This nomenclature is similar to that currently used by a number of other certification programs and is intended to promote standardization and transparency within the seed potato industry. It is expected that this change will be in effect after the 2018 Idaho legislative session.
— Alan Westra, Idaho Crop Improvement Association, southeast area manager
Montana
Montana seed potato acreage is up slightly to 10,355 acres, which represents a minor increase when compared to 10,220 acres in 2017.
Russet Burbank is still the dominant variety and is holding steady at 3,921 acres. Clearwater acreage continues to rise dramatically with 1,016 acres this season compared to 698 last year, representing a 31 percent increase. Umatilla is the second most widely produced variety in Montana but was down 16 percent from 1,789 acres in 2017 to 1,509 acres in 2018. Ranger Russet acreage is steady at 1,172 acres and the Norkotah Russet selections were up 13 percent to 997 acres. Alturas continue to decline, from 637 acres in 2017 to 588 acres in 2018. Standard Norkotah acreage dropped precipitously and now only accounts for 54 acres in Montana. There are a total of 57 varieties of potatoes registered for certification.
2018 was a year of early extremes followed by warm, mild conditions. Some Montana growers were planting in early May and some got a late start due to wet conditions in mid-May, finishing planting in early June. In the Gallatin and Beaverhead regions, the early planted potatoes received a hard frost on June 12 and the later planted potatoes ended up staging very similar to the earlier planted potatoes. The rest of the summer we had ideal growing conditions throughout the state with plenty of warm days but no extreme heat or storms. This set the Montana crop up with strong yields of extremely uniform tubers and an optimal size profile.
In Montana, production of seed with very low virus levels is enhanced by our growers’ practice of planting all Generation 1 potatoes as family units. Each unit is planted with the daughter tubers from a single nuclear generation plant. During the summer, each unit is 100 percent tested for PVY. If a test comes back positive, the whole unit is removed. In addition to PVY, we test for PVX and PVA in the winter grow-out, which will be planted in November on the island of Oahu, Hawaii. The annual Montana Seed Potato Seminar was scheduled for Nov. 7-8 at the Holiday Inn Downtown, Missoula, Montana. Call 406-994-3150 for more information.
— Nina Zidack, director, Montana Seed Certification Program
Oregon
Growing a successful seed potato crop means navigating two major variables: weather and disease/pest pressure. For the most part, growers were able to clear these hurdles in the 2018 season.
Growers nationwide didn’t experience anything apart from the ordinary cycles of warm/cool and wet/dry but there were a few exceptions. Andrew Houser, manager of the Colorado Potato Certification Service, said weather conditions in the San Luis Valley were “very unique.”
“In typical years, winter temperatures can drop to 20 or 30 below zero. This past winter, temperatures rarely dropped below zero. This was in large part due to lack of snowpack in the surrounding mountain ranges. The warm temperatures continued through May and June, resulting in a fast growing potato crop,” Houser said.
Idaho growers reported a tough planting season due to heavy rains, while in Michigan excess moisture bogged down the harvest.
In general, growers were able to dodge severe problems with the usual roster of threats, including PVY, dickeye, blackleg, Colorado potato beetle and others.
— Jeff McMorran, Oregon Seed Certification Service
Washington
A total of 3,681 acres of seed potatoes were entered for certification during the 2018 growing season. This is a 155-acre increase from last year. The total acres planted include 182 different potato varieties ranging in size from partial acre plots to 118-acre fields. Most seed lots are less than 20 acres in size and include numbered clones, table stock, processing and heirloom variety potatoes. This year saw 1,126 individual seed lots entered for certification from 10 separate farms.
Pacific Northwest weather and Washington’s maritime climate in particular, with cool nights, warm temperatures during the day along with supplemental rainfall, provided for ideal growing conditions this season. Late blight and black leg disease pressure was slight to non-existent. Washington State Department of Agriculture (WSDA) staff noted PVY in 31 out of 11,126 seed lots entered for certification, and noted insect vectors from few to none during field inspections. Complete field inspection results are available at https://agr.wa.gov/PlantsInsects/PlantCertification/PlantCertification.aspx
Harvest began after Labor Day with inopportune rains and other factors slowing harvest for a time. Harvest was complete by mid-October. Growers enjoyed average to above average yields with generally good quality, size and condition of seed lots going into storage. Seed shipments to southern climates began in late fall and will continue into the winter months, with the majority of seed to be shipped in early spring.
— John L. Wraspir, plant services program supervisor of WSDA Plant Protection division
