Interim Report: Evaluation of the Ecosystem Services and Profitability of Perennial Cereal Grain Crops (PCGC) for Integrated Grain and Forage Production in Alberta
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Funded by Results Driven Agriculture Research (RDAR)
Collaborators: Peace Country Beef & Forage Association (PCBFA), University of Alberta, Mackenzie Applied Research Association (MARA), Gateway Research Organization (GRO), Battle River Research Association (BRRG), Chinook Applied Research Association (CARA)
This dual-purpose research study, initiated in 2022, focused on both grain and forage production. The research extensively examined the potential of perennial cereal-legume intercropping systems to provide both high-quality forage and grain yield. We used two Perennial Cereal Grain Crops (PCGC) and three legumes. Key focus areas included forage productivity and quality, ecosystem functions (such as nitrogen fixation by legumes and subsequent transfer to perennial grain yields), and the effects of the cropping system on soil properties and overall soil health. By investigating these dual-purpose objectives, the study aims to enhance sustainable agricultural practices, improve long-term productivity, and promote soil health across diverse agroecosystems in Alberta.
This province-wide project, coordinated by PCBFA, established research plots at six locations: Fairview, Breton, Westlock, Fort Vermilion, Forestburg, and Oyen. The project is led by Cosmas Ugwu, a Ph.D. candidate at the University of Alberta, working under the supervision of Dr. Guillermo Hernandez and Dr. Akim Omokanye. Fieldwork began in 2022, marking the first production year, and concluded in the summer of 2024, the third production year. This report highlights the findings from the Fairview Research Farm (PCBFA). A comprehensive summary of results and take-home messages from all sites will be released in 2026.
Objectives
In the final field year (2024), we evaluated the second-year productivity of forage and grain from intercropping PCGC with legumes, seeded in both alternate and same-row seeding methods. Additionally, we measured the nitrogen fixed by legumes within forage stands and assessed soil health improvements by analyzing key indicators, including chemical, physical, and biological properties.
Methodology
The trial took place at the Fairview Research Farm (FRF). The experimental design was a randomized complete block design with four replications in small plots measuring 8 m x 1.14 m. Seeding was carried out using a 6-row Fabro Plot Drill equipped with disc-type openers on 23 cm row spacing, complete with side banding. Table 1 shows treatments tested, establishment and management.
Specific field work carried out in 2024 included:
Bi-weekly Normalized Difference Vegetation Index (NDVI), soil moisture, soil compaction, and temperature measurements.
15N isotope application for nitrogen fixation measurements in early spring.
Plant tissue analyses on the perennial cereals.
Soil sampling to determine nitrate concentration.
Forage and grain yield estimation (dual purpose utilization).
In Field Observations
At the Fairview Research Farm:
Ergot was present in perennial pye heads, but no disease was observed in perennial wheat.
The growing season started dry, but received 240 mm of precipitation, with high temperatures early in the season that persisted through summer.
In 2022, ACE-1 perennial rye was a lush, well-established stand.
In 2023 and 2024, severe winterkill in ACE-1 perennial rye led to reduced regrowth.
Perennial wheat showed resilience, maintaining strong growth and foliage throughout the season.
Legume varieties were scanty in many same-row-seeded plots, making them hard to locate.
Sparse ACE-1 perennial rye stands and winterkill increased weed pressure, which is expected to continue into 2025 due to the lack of herbicide applications in 2023 and 2024.
Results
Forage Dry Matter (DM) Yield
Figure 3. Forage dry matter yield (lbs/ac) at Fairview Research Farm in Alternate Row (AR), Same Row (SR), or Monocrop seeding methods for 2024.
There was a noticeable trend in Forage Dry Matter (DM) yield and grain yield across different treatments and seeding methods.
Figure 3 shows that the highest Forage Dry Matter yield was found in the Kernza wheatgrass-Alfalfa treatment (8009 lbs/ac), followed by Kernza wheatgrass-Sainfoin (6703 lbs/ac) and Kernza wheatgrass-White Clover (6443 lbs/ac).
The monocrop Kernza wheatgrass treatment yielded slightly lower forage (6475 lbs/ac) but still higher than the ACE-1 perennial rye treatments (Figure 3).
In general, Kernza wheatgrass treatments produced higher Forage Dry Matter yields than ACE-1 perennial rye treatments.
PCGC Grain Yield at Fairview Research Farm for 2024
Figure 4. Grain yield (lbs/ac) of Kenza® wheatgrass and ACE-1 perennial rye at Fairview site in Alternate Row (AR) and Same Row (SR), or Monocrop seeding methods in 2024.
For grain yield, the ACE-1 perennial rye-Sainfoin treatment had the highest yield at 1,230 lbs/ac, followed by ACE-1 perennial rye-White Clover (584 lbs/ac) and ACE-1 perennial rye-Alfalfa (299 lbs/ac). The ACE-1 perennial rye Monocrop treatment produced 419.1 lbs/ac.
In contrast, the Kernza® wheatgrass treatments had significantly lower grain yields:
Kernza® wheatgrass-Alfalfa: 250.4 lbs/ac
Kernza® wheatgrass-Sainfoin: 227.3 lbs/ac
Kernza® wheatgrass monocrop: 206.2 lbs/ac
While Kernza® wheatgrass treatments excelled in forage dry matter yield, the ACE-1 perennial rye treatments performed better in grain yield.
Soil Mineral Nitrogen
The residual nitrogen levels after the 2023 fall harvest showed notable differences in ammonium (NH4-N) and nitrate/nitrite (NO2+NO3-N).
Ammonium levels were low across all treatments, ranging from 2 to 4 mg/kg.
Nitrate levels were higher in ACE-1 perennial rye-Clover and ACE-1 perennial rye Monocrop, ranging from 18 to 32 mg/kg.
The higher nitrate levels, especially in the ACE-1 perennial rye monocrop, indicate that nitrogen remained in a form easily usable by plants. This residual nitrogen could potentially reduce the need for synthetic fertilizers in the future.
Forage Quality
The 2024 PCGC project at the Fairview Research Farm showed significant differences in forage nutritive value across treatments.
Kernza® wheatgrass treatments combined with alfalfa and white clover had slightly higher Crude Protein (CP) than the ACE1 perennial rye cereal treatments. For example, Kernza® wheatgrass -Alfalfa had the highest CP at 11.5% (Table 1).
In terms of fiber content, ACE-1 perennial rye combined with sainfoin or white clover had the lowest Neutral Detergent Fiber (NDF) (53.2%) and Acid Detergent Fiber (ADF) (40.2%), which suggests better intake and digestibility.
Conversely, Kernza® wheatgrass Monocrop and Kernza® wheatgrass treatments with white clover had the highest Total Digestible Nutrients (TDN) at 56%.
Neutral Detergent Fiber (NDF) digestibility at 48 hours (NDFD-48) was highest in Kernza® wheatgrass -White Clover and Kernza® wheatgrass Monocrop, indicating improved digestibility over time (Table 1).
These results highlight the nutritional diversity among forage treatments, offering useful insights for optimizing livestock feed strategies.
Conclusion
The 2024 PCGC project at the Fairview Research Farm revealed distinct trends in forage and grain productivity. Kernza® wheatgrass consistently outperformed ACE-1 perennial rye in forage dry matter yield, especially under same-row seeding configurations. In contrast, ACE-1 perennial rye produced higher grain yields, highlighting its potential as a grain-focused perennial cereal. These results suggest that Kernza® wheatgrass is better suited for forage production, while ACE-1 perennial rye may be more favourable for grain yield, particularly when intercropped with legumes such as sainfoin and white clover.
Soil health indicators, including nitrate levels, also demonstrated the beneficial effects of legume intercropping on soil fertility. These early findings point to a promising approach for integrated forage-grain systems that enhance both productivity and sustainability.
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