Hay Test Research
November 29, 2023
University of Idaho Extension Educator Sawyer Fonnesbeck was stumped twice by the same question during presentations he gave early this year about the importance of testing alfalfa hay.
Growers who heard him speak at Idaho Range Livestock Symposium sessions asked him to estimate how long alfalfa test results remain valid. Fonnesbeck, a livestock production and ruminant nutrition Extension educator based in Oneida County, had no answer, unaware of any research on the subject conducted in or near Idaho.
Seeking to generate his own data in response to the growers’ question, Fonnesbeck has launched a research project, using a $3,000 mini-grant through Idaho Sustainable Agriculture Research and Education (SARE) Professional Development. Fonnesbeck will discuss his ongoing study on how long hay retains its nutritional value in various storage conditions, as well as advice for incorporating water-damaged or moldy hay into rations, during East Idaho Beef School, which will be offered at three locations throughout the region later this month.
The three schools will be conducted at the UI Extension county offices:
- Nov. 28 in Blackfoot (Bingham County) — 412 W Pacific St from 6-8 p.m. MT
- Nov. 29 in Montpelier (Bear Lake County) — 21620 U.S. Highway 30 from 6-8 p.m. MT
- Nov 30. In Malad (Oneida County) — 459 Main St from 6-8 p.m. MT
RSVP by emailing cwillmore@uidaho.edu in Blackfoot, jhatch@uidaho.edu in Montpelier or sfonnesbeck@uidaho.edu in Malad. There is no fee to attend any of the schools and dinner is included. Other topics covered will include an update about the national Beef Quality Assurance program audit and the use of dart guns for doctoring cattle.
Fonnesbeck hopes beef school participants will give him feedback on his study’s setup and ideas for possible spinoff projects in the future. For his study, Fonnesbeck purchased 12 small hay bales from three different producers and divided them into three lots – one stack is being stored on bare ground with no covering, another is being stored on a pallet with a tarp covering the top and the final stack is being kept in a shed. Fonnesbeck will conduct baseline testing, followed by bimonthly testing, to determine how well each haystack retains its nutritional value.
“My theory is within the hayshed, the nutritional value is going to have a downward slope, but it’s going to be very moderate,” Fonnesbeck said. “My hay uncovered and on bare ground, I think it’s going to have a steeper decline in nutritional value. What will be interesting to see is how steep the downward slope of the nutritional value actually is for each storage type. That is the current unknown piece of the puzzle.”
The data should help producers better balance rations to meet the nutritional needs of livestock using hay that’s been stored for several months.
Producers may add nutrient supplements to their rations to offset any losses in nutritional value, or simply feed cattle more hay.
In addition to time, rain can deplete the nutritional value of hay. A light rain shortly after cutting, when the hay still retains most of its moisture, likely won’t cause much damage. After cut hay has had time to dry, however, rain may leach soluble sugars and carbohydrates from plants. Furthermore, if a rainstorm elevates the moisture level of dried alfalfa back above 50% cellular respiration may resume, which uses stored energy within the plant that would otherwise benefit livestock. Fonnesbeck estimates two-thirds of the hay in Oneida County sustained some rain damage after cutting this season.
“If you are selling rained on hay, or feeder hay, you are probably going to lose at least $50 per ton, and probably more,” Fonnesbeck said.
If hay is soaked for too long and a producer can’t get it to dry, it may become moldy. Certain kinds of mold are toxic to cattle, and Fonnesbeck recommends testing for mold toxicity if mold damage is widespread. Otherwise, he suggests blending in moldy hay with better alfalfa, allowing cattle to pick out any good hay from a moldy bale.
Fonnesbeck advises using feeder hay in the late fall and early winter and switching to high-quality hay for bred heifers during calving season, from late February to early April, sustaining them during peak lactation and enabling them to recuperate to breed again later in the spring.
About the University of Idaho
The University of Idaho, home of the Vandals, is Idaho’s land-grant, national research university. From its residential campus in Moscow, U of I serves the state of Idaho through educational centers in Boise, Coeur d’Alene and Idaho Falls, nine research and Extension centers, plus Extension offices in 42 counties. Home to nearly 11,000 students statewide, U of I is a leader in student-centered learning and excels at interdisciplinary research, service to businesses and communities, and in advancing diversity, citizenship and global outreach. U of I competes in the Big Sky and Western Athletic conferences. Learn more at uidaho.edu.