Sierra Testing Service uses the Near-Infrared Reflectance (NIR) Spectroscopy to analyze forage samples. The NIR analysis is a nondestructive analytical technique that uses the optical characteristics of a sample to measure major constituents in compounds. Research at the USDA experiment station in Beltsville, Maryland resulted in the development of a machine that scans a finely ground sample. The machine with the use of a computer correlates the measurements with the chemical compositions done in a laboratory. The machine is calibrated to the different hays and grains in a specific region. When calibrated properly, the NIR analysis will provide high speed analysis with high repeatability.

Sierra Testing Service has been a member of the National Hay Testing Association since 1987. We are now a part of The National Forage Testing Association, and received the NFTA Proficient Laboratory for 2010. We have participated in trials with the University of California Extension Service and the University of Nevada Extension Service. Sierra Testing Service was rated the number one lab in a repeatability study completed by the University of Nevada Extension Service. We are currently members of the California Alfalfa and Forage Association, California Hay Testing Consortium and a Associate member of the High Mountain Hay Growers Association. We strive to support groups that have goals of helping the industry in marketing and research.


Sierra Testing Service was started in 1983 by Stan Seifert. At the time he was a part of the family dairy in Acampo, California. The dairy was having a difficult time getting consistent results that correlated with milk production. Stan searched through the procedures available in the laboratory industry. He found that the Near-Infrared System results worked well in the dairy rations and the repeatability was excellent.

Stan Seifert is a 1965 graduate of California State University at Fresno with a Bachelor of Science in Dairy Science. He has 30 years experience in dairy and farming operations. Stan purchased and hauled alfalfa hay from Oregon, Nevada, Arizona, and California for the family dairy. Currently he operates alfalfa ranches in McArthur, California and an almond orchard in Acampo, California. This background is an excellent resource for the alfalfa hay industry.


His son Steve joined the operation in 1986. Steve is a 1986 graduate of the California State University at San Luis Obispo with a Bachelor of Science degree in Agri-business. Steve grew up on the family dairy and was involved in the operation. Sierra Testing Service is currently operated by Stan, his wife Judy and son, Steve.

Sierra Testing Service

Stan and his son, Steve Seifert