Potatoes have been an important Klamath Basin crop since the 1920's. The current crop includes about 7,000 acres in Klamath County, Oregon and 8,000 acres in Northern Modoc and Siskiyou Counties, California. Crops are grown for seed (1,000 acres), chip processing (5,500 acres), and fresh market sales (8,500 acres). Seed crops are used for local commercial crops or marketed in Kern County and other California production areas. Fresh market crops are processed in about 8 local packing sheds and sold primarily in major California population centers. Small and off-grade potatoes are used for cattle feed or for flakes or granules in a local processing facility.
Climatic conditions are a major deterrent to high yields and quality in local crops. Foliar injury due to frosts was a serious limitation until solid-set irrigation was adopted in the 1960's. While sprinkler irrigation protects crops down to 25 degrees F for short duration frost conditions, irrigation for frost protection can contribute to other problems related to excessive soil moisture. A short growing season in the best of times, limits yields, particularly for late maturing varieties such as Russet Burbank, which dominated Klamath Basin production until the last 5-7 years.
Nematodes and related diseases have also been serious constraints for local potato crops. Root-knot nematode damage to potatoes was a major problem that led to the establishment of the KES in the late 1930's. This pest is still a major concern in the region. Various chemical control measures, developed or evaluated at the KES, have kept the problem in check for the majority of crops, but serious losses to root-knot nematode still occur.
Spraign or corky ringspot caused by tobacco rattle virus and vectored by the stubby-root nematode, has been another serious problem for potato crops on mineral soil in the Klamath Basin. Aldicarb provided cost-effective control of this problem until this product was withdrawn in 1990. No effective alternative has been identified to date. Fields with a history of corky ringspot infection have been abandoned for potato production. The 1996 reintroduction of Aldicarb for potato production will not benefit Klamath Basin crops due to the limitation of 150 days from application to harvest. Most local crops are harvested less than 130 days after planting.
Prior to 1997, potato late blight was absent from the Klamath Basin. However, several fields were infected with late blight in both 1997 and 1998. The result has been a significant increase in production costs as more rigorous protective fungicide programs are implemented.
One very serious problem for the North American potato industry is currently absent in the Klamath Basin. Colorado potato beetles do not occur in the region. While the reasons for their absence are unknown, they are not missed, and they are certainly unwelcome. Other insect pests, including the green peach aphid, are less prevalent than in other production regions.
As recently as the mid-80's, Klamath Basin crops were principally Russet Burbank with a minor acreage of Norgold Russet for early harvest and a few Kennebec acres for chip processing. In 1995, Russet Burbank accounted for less than 50% of production. Russet Norkotah has replaced Norgold entirely, and has replaced a significant portion of the Russet Burbank crops. Kennebec has been replaced by Snowden, Chipeta, and Frito-Lay varieties. Minor acreages of Yukon Gold and several red-skinned varieties are also grown.
Two new releases from the Oregon potato variety development program, Mazama and Klamath Russet, are excellent candidates for fresh market production in the Klamath Basin. Klamath Russet was grown in small commercial scale lots in 1999-2001 with very good results. Limited seed production will prevent large commercial evaluation until about 2004. Mazama, a bright red-skinned selection that produces relatively high yields of small tubers is being evaluated in small commercial lots for the first time in 2002. Performance of these selections in trials at KES and the UC Davis Tulelake Field Station were instrumental in their release.
The curtailment of irrigation supply for the 2001 season in the Klamath Reclamation Project resulted in the loss of about 10,000 acres of fresh market potatoes that would have been evenly supplied to the market from October through early July. The marketing season for the 2001 fresh-market potato crop has set record prices. Through April 2002, return to growers for fresh market russets held quite steady at about $8.00/cwt. Since then prices have increased to over $12.00/cwt. The opportunity cost to the local industry, in terms of net profit to growers for the loss of 10,000 acres of production exceeds $20 million. Effects on loss of market share to traditional customers for local crops may become evident during the marketing season for the 2002 crop. Two prominent packing sheds in the basin were forced out of business by the irrigation curtailment.