Oat Variety Trial 2024
This research was funded by USDA-NIFA, Walton Family Foundation, Albert Lea Seed House, Welter Seed and Honey Co., SDSU Seed Foundation, UW Foundation Seeds and Zabel Seeds.
In a Nutshell:
- 16 oat varieties were screened at four Iowa State University research farms.
Key Findings:
- Across varieties and sites, average oat yield was 125 bu/ac and average test weight was 36 lb/bu.
- Saddle scored the highest grain yield, Antigo scored the highest test weight.
Heads of oats just before harvest.
Background
Oats have low input requirements and beneficial effects on succeeding crops in a rotation. They can be used for grain and straw production, as a companion crop to establish hay and pastures, or for early-season forage as hay or haylage. Because of their relatively short growing season, oat production opens up numerous field management options for the remainder of the season. Perhaps reflecting these benefits, oat production has increased in Iowa in recent years. In 2024, 210,000 acres of oats were planted in Iowa, according to the USDA-National Agricultural Statistics Service [1]. This is up from 200,000 acres in 2023, and above other recent plantings of 130,000 acres in 2022, and 180,000 acres in 2021. Furthermore, 120,000 acres were harvested in 2024 (57%), up from 95,000 acres harvested in 2023 (47%). The average yield in Iowa in 2024 was 86 bu/ac; the average yield of the previous 3 years was 76 bu/ac [1].
Oat grain and straw yield and attributes, like lodging propensity, can vary by variety and growing conditions. This means that oat variety trials at sites across the state are important tools for farmers who grow oats. Since 2015, PFI has helped organize oat and other small grains variety trials at Iowa State research farms around the state, and four sites participated this year.
Methods
Variety trials were conducted at four locations in 2024: ISU Northern Research Farm in Kanawha; ISU Ag Engineering and Agronomy Farm in Boone; ISU Northeast Research Farm in Nashua; and ISU Southwest Research Farm in Greenfield. These variety trials build on previous trials conducted at Kanawha, Charles City, Boone, Nashua and Greenfield from 2015–2023 [2 – 10]. Information about each of the varieties trialed in 2024 can be found in Table 1.
Oat management information is provided with the results from each location. No herbicides or insecticides were applied at any location during the oat growing season. Statistical significance is determined at 90% confidence level and means separations are reported using Tukey’s least significant difference (LSD). Data were analyzed by location, and varieties are listed in alphabetical order at each location. Reported yields are corrected for 13% moisture. Rainfall and temperature data were modeled for the site location from NASA weather data by the NASA-power climatology R package [11], [12].
Results and Discussion
Rainfall in 2024 was above 10-year averages at all sites during the oat growing season. Recent years had been affected by drought, but those trends were reversed by the large amounts of rain that fell in the spring and early summer of 2024 [13].
Compared to U.S. national (75 bu/ac) and state of Iowa (86 bu/ac) average yields, all four ISU sites had much higher yields [1]. Furthermore, 2024 yields were generally higher than the three-year averages (2022-2024) from the same sites (Tables 2-5). Across all sites, the five highest-yielding varieties were Saddle (151 bu/ac), Rushmore and MN Pearl (both 136 bu/ac), and Warrior and Reins (both 134 bu/ac). Saddle was the run-away yield champion, yielding significantly more than any other variety across all sites. At individual sites, these five varieties tended to be among the highest yielding varieties, but this difference was not consistently statistically significant. Goliath (97 bu/ac) and Antigo (108 bu/ac) were the lowest-yielding varieties, although Antigo consistently scored the highest test weight, averaging 38 lb/bu.
Compared to the previous three years at the ISU sites, test weights were higher in 2024. The standard minimum test weight that many companies require for food grade oats is 38 lb/bu. All sites had at least one variety reach the food-grade threshold, and Nashua and Greenfield each had six varieties that reached this threshold. This is a reversal of the general pattern from the last three years of tests at ISU sites, which have had Nashua and Greenfield underperforming in terms of number of varieties reaching food-grade test weight, compared with Kanawha and Boone. This could be because the previous three summers in Iowa have been dry, while 2024 was wet. Kanawha had the lowest average test weight and had only one variety (Antigo) reach food-grade test weight, but it had the highest average yield across varieties. Kanawha had the longest period between seeding and harvest (140 days).
Boone had the lowest average yield of all the sites, and only two varieties (Shelby and SD Momentum) reached food quality test weight at Boone. These relatively poor results may be attributable to the massive incidence of lodging there: 80% of all the oat plants grown there during this trial were assessed to have lodged. The late harvest (Boone was the only site harvested in August) probably contributed to the high rate of lodging.
Rushmore was the best all-around performing variety, producing the second highest yields (average 136 bu/ac), tying for the highest test weights (38 lb/bu), and reaching the food-grade standard at both the Nashua and Greenfield test sites. It was also the third-highest straw-producing variety (2.2 tons/ac) at Nashua, the only site that measured straw yields.
PFI plans to continue oat variety trials in future years at ISU research farms.
ISU Northern Research Farm, Kanawha
Previous crop: Soybeans
Replications: 3
Harvested plot size: 5 ft × 47 ft
Fertilizer applied: 35 lb/ac N as UAN on March 12, 2024
Planting date: March 12, 2024
Row spacing: 7.5 in.
Seeding rate: 4 bu/ac
Seeding depth: 1 in.
Harvest date: July 30, 2024
ISU Ag Engineering and Agronomy Farm, Boone
Previous crop: Soybeans
Replications: 3
Harvested plot size: 13.5 ft × 48 ft
Fertilizer applied: 39 lb N/ac; 100 lb P/ac; 40 lb K/ac; 37 lb S/ac on Apr. 10, 2024
Planting date: April 10, 2024
Row spacing: 7.5 in.
Seeding rate: 4 bu/ac
Seeding depth: 1 in.
Harvest date: Aug. 8, 2024
ISU Northeast Research Farm, Nashua
Previous crop: Soybeans
Replications: 3
Harvested plot size: 8.125 ft x 125 ft
Fertilizer applied: 30 lb N/ac as urea on March 7, 2024
Tillage: Field cultivator to incorporate urea on March 11, 2024
Planting date: March 11, 2024, followed by cultipacking
Row spacing: 7.5 in.
Seeding rate: 4 bu/ac
Seeding depth: 1.5 in.
Harvest date: July 19, 2024 (grain) followed by July 22, 2024 (straw)
ISU Southwest Research Farm, Greenfield
Previous crop: Soybeans
Replications: 3
Harvested plot size: 5 ft × 50 ft
Fertilizer applied: 35 lb N/ac as urea on March 12, 2024
Tillage: Incorporated urea with disk
Planting date: March 13, 2024
Row spacing: 7.5 in.
Seeding rate: 4 bu/ac
Seeding depth: 1.5 in.
Harvest date: July 17, 2024
Funding Acknowledgement
This work is supported by the Agriculture and Food Research Initiative, grant number F9000315202081 from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the U.S. Department of Agriculture.
We would also like to express our gratitude to Albert Lea Seed House, Welter Seed and Honey Co., Zabel Seeds, South Dakota State University Seed Foundation and University of Wisconsin Foundation Seeds for donating seed for these variety trials.
References
[1] “USDA/NASS QuickStats Ad-hoc Query Tool.” Accessed: Sep. 11, 2024. [Online]. Available: https://quickstats.nass.usda.gov/
[2] S. Gailans and S. Carlson, “Oat Variety and Fungicide Trials,” Practical Farmers of Iowa. Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-and-fungicide-trials/
[3] S. Gailans and S. Carlson, “Oat Variety Trials 2016,” Practical Farmers of Iowa. Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-trials-2016/
[4] S. Gailans and S. Carlson, “Oat Variety and Fungicide Trials 2017,” Practical Farmers of Iowa. Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-and-fungicide-trials-2017/
[5] S. Gailans, “Oat Variety Trial 2018,” Practical Farmers of Iowa. Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-trial-2018/
[6] S. Gailans and S. Carlson, “Oat Variety Trial 2019,” Practical Farmers of Iowa. Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-trial-2019/
[7] S. Gailans and L. English, “Oat Variety Trial 2020.” Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-trial-2020/
[8] S. Gailans and L. English, “Oat Variety Trial 2021,” Practical Farmers of Iowa. Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-trial-2021/
[9] S. Gailans, “Oat Variety Trial 2022,” Practical Farmers of Iowa. Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-trial-2022/
[10] S. Gailans and E. Link, “Oat Variety Trial 2023,” Practical Farmers of Iowa. Accessed: Sep. 11, 2024. [Online]. Available: https://practicalfarmers.org/research/oat-variety-trial-2023/
[11] A. H. Sparks, “nasapower: A NASA POWER Global Meteorology, Surface Solar Energy and Climatology Data Client for R,” J. Open Source Softw., vol. 3, no. 30, p. 1035, Oct. 2018, doi: 10.21105/joss.01035.
[12] A. Sparks, nasapower: NASA-POWER Data from R. (2024). [Online]. Available: https://CRAN.R-project.org/package=nasapower
[13] “Map Archive | U.S. Drought Monitor.” Accessed: Sep. 11, 2024. [Online]. Available: https://droughtmonitor.unl.edu/maps/maparchive.aspx