This research was funded by the following organizations:
- Walton Family Foundation
- General Mills
- Grain Millers, Inc.
- Albert Lea Seed House
- Sustainable Food Lab
- Welter Seed and Honey Co.
- Kuehl Seed Farm
- UMN Foundation
- SDSU Seed Foundation
- Zabel Seeds
In a Nutshell
- 18 oat varieties were screened at four Iowa State University research farms and two varieties were compared on one organic commercial farm.
Key Findings
- Across varieties and sites, average oat yield was 121 bu/ac. Saddle had the highest yield at three of the four research farms.
- Streaker (hulless variety) scored the highest test weight at each location, however it was also the lowest yielding variety at each location. Sumo, Shelby 427 and Rushmore (hulled varieties) made food grade test weight specifications at three of the four research farms.
Background
Careful management and proper choice of variety can make oats a profitable crop due to their low input requirements and beneficial effects on succeeding crops in a rotation. Oats 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 oats are harvested in late July to early August, field management options for the remainder of the season are numerous. These include establishment of a perennial forage or summer cover crop, as well as an opportunity for mid-season manure application. In 2020, 240,000 acres of oats were planted in Iowa according to the USDA-National Agricultural Statistics Service. The state average yield for the year was 78 bu/ac; the five-year average yield is 70 bu/ac.
Planting oats before April 15 is recommended for optimal yields in Iowa. This helps avoid exposure to warmer weather during grain fill. Test weight is the most commonly used indicator of grain quality. High test-weight varieties should be chosen by growers who intend to market oat grain to food-grade buyers.
Oat growth is regularly affected by rust and barley yellow dwarf virus. Variety resistance to these diseases should be considered. Another option is the use of a foliar fungicide applied at Feekes 9 growth stage, defined as flag leaf emerged with ligule visible.
Oat variety trial plots at the ISU Northeast Research Farm near Nashua on June 29, 2020. Photo credit: Margaret Smith
Methods
Variety trials were conducted at five locations in 2020: ISU Northern Research Farm in Kanawha; ISU Ag Engineering and Agronomy Farm in Boone; ISU Northeast Research Farm in Nashua; ISU Southwest Research Farm in Lewis; Ron Rosmann’s organic farm in Harlan. These variety trials build on previous trials conducted at Kanawha, Charles City, Boone and Nashua from 2015-2019.[1–5] Information about each of the varieties trialed in 2020 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. Entries were screened for crown rust, barley yellow dwarf virus and septoria leaf blight by Margaret Smith from Albert Lea Seed House and Ken Pecinovsky in late June at Nashua only.
Data were analyzed using JMP Pro 15 (SAS Institute Inc., Cary, NC). Statistical significance is determined at P ≤ 0.10 level (unless otherwise noted) and means separations are reported using Tukey’s least significant difference (LSD).
Results and Discussion
Data were analyzed by location, and varieties are listed in order of yield performance at each location. Reported yields are corrected for 13% moisture. A “percentage of test average” calculation is included to aid in comparing varieties at each location. Rainfall and temperature data were accessed from the nearest weather station.[6] Except for at Nashua, rainfall in 2020 was well below historical averages.
Streaker, a hulless variety, routinely yielded least but always scored the highest test weight at each location (>42 lb/bu). Several varieties made a test weight of 38 lb/bu – the standard minimum that many food companies require before dockage is applied. (A test weight of 36 lb/bu is a minimum processing facilities can use for food-grade milling.) Ratings conducted by Smith and Pecinovsky at the Nashua location on June 29 indicated very low disease incidence (data not shown).
ISU Northern Research Farm, Kanawha
- Previous crop: Soybeans
- Replications: 3
- Harvested plot size: 5 ft x 47 ft
- Fertilizer applied: 65 lb N/ac as urea on Apr. 2
- Tillage: Soil finisher on Apr. 2 and Apr. 7
- Planting date: Apr. 7, followed by cultipacker
- Row spacing: 7.5 in.
- Seeding rate: 4 bu/ac
- Seeding depth: 1 in.
- Harvest date: July 24
ISU Ag Engineering and Agronomy Farm, Boone
- Previous crop: Soybeans
- Replications: 3
- Harvested plot size: 5 ft x 51.5 ft
- Fertilizer applied: 30 lb N/ac; 100 lb P/ac; 25 lb S/ac; 2.5 lb Zn/ac as MESZ on March 31
- Tillage: Field cultivator on Apr. 2
- Planting date: Apr. 2
- Row spacing: 7.5 in.
- Seeding rate: 4 bu/ac
- Seeding depth: 1 in.
- Harvest date: July 28
ISU Northeast Research Farm, Nashua
- Previous crop: Soybeans
- Replications: 3
- Harvested plot size: 8 ft x 93 ft
- Fertilizer applied: 30 lb N/ac urea; 20 lb P as TSP; 35 lb K/ac as potash on March 23
- Tillage: Field cultivator on March 30 and 31
- Planting date: March 31, followed by cultipacker on Apr. 2
- Row spacing: 7.5 in.
- Seeding rate: 4 bu/ac
- Seeding depth: 1 in.
- Harvest date: July 20
ISU Southwest Research Farm, Lewis
- Previous crop: Soybeans
- Replications: 3
- Harvested plot size: 5 ft x 55 ft
- Fertilizer applied: 70 lb N/ac as urea
- Tillage: Disked on Apr. 2
- Planting date: Apr. 7, 2020, followed by cultipacker
- Row spacing: 7.5 in.
- Seeding rate: 4 bu/ac
- Seeding depth: 1 in.
- Harvest date: July 30
Ron Rosmann Farm, Harlan
- Previous crop: Soybeans
- Replications: 4
- Harvested plot size: 13.5 ft x 1,500 ft
- Fertilizer applied: 4 tons/ac composted hog and cattle manure on March 21
- Tillage: Disked twice on March 21
- Planting date: Apr. 1, undersown with alfalfa, red clover and orchardgrass
- Row spacing: 7.5 in.
- Seeding rate: 4 bu/ac
- Seeding depth: 1 in.
- Harvest date: July 21 (swathed); July 22 (picked up)
References
- Gailans, S., S. Carlson, K. Pecinovsky and B. Lang. 2015. Oat Variety and Fungicide Trials. Practical Farmers of Iowa Cooperators’ Program. https://practicalfarmers.org/research/oat-variety-and-fungicide-trials/ (accessed October 2020).
- Gailans, S., S. Carlson, M. Schnabel, K. Pecinovsky, B. Lang and W. Johnson. 2016. Oat Variety Trials 2016. Practical Farmers of Iowa Cooperators’ Program. https://practicalfarmers.org/research/oat-variety-trials-2016/ (accessed October 2020).
- Gailans, S., S. Carlson, M. Schnabel, K. Pecinovsky, B. Lang and W. Koehler. 2017. Oat Variety and Fungicide Trials 2017. Practical Farmers of Iowa Cooperators’ Program. https://practicalfarmers.org/research/oat-variety-and-fungicide-trials-2017/ (accessed October 2020).
- Gailans, S., S. Carlson, M. Schnabel, K. Pecinovsky and W. Johnson. 2018. Oat Variety Trial 2018. Practical Farmers of Iowa Cooperators’ Program. https://practicalfarmers.org/research/oat-variety-trial-2018/ (accessed October 2020).
- Gailans, S., S. Carlson, M. Schnabel, K. Pecinovsky and W. Koehler. 2019. Oat Variety Trial 2019. Practical Farmers of Iowa Cooperators’ Program. https://practicalfarmers.org/wp-content/uploads/2019/12/PFI2019_ResearchReport_Oat-Variety-Trial.pdf (accessed October 2020).
- Iowa Environmental Mesonet. 2020. Climodat Reports. Iowa State University. http://mesonet.agron.iastate.edu/climodat/ (accessed October 2020).