Funded by the Canadian Agricultural Partnership
(Government of Canada and Government of Alberta)
Feeding livestock through the winter is costly to production when pastures are not grazable and feed intake generally increases. Methods to extend potential grazing days towards the end of the growing season, while pastures go dormant, can help to preserve winter feed resources. Common cereals grown for feed include barley, oats, rye, triticale, and wheat. One advantage to a spring-winter cereal mix is the spring cereal can be harvested, while allowing the regrowth of the winter cereal to be used as winter pasture when perennial pastures are entering dormancy.
Objective
The objective of this study was to determine forage yield and nutritional quality differences between spring planted spring-winter cereal mixtures used for silage, annual pasture, or fall pasture compared to annual monocrop varieties.
Methods
Location: This project was conducted at Garth Isaac’s farm in Teepee Creek, Cropping history: Summer fallow
Experimental design and treatments: A randomized complete block design was used in four replications on small plots measuring 8m x 1.14m and 0.65m alleyways between plots. Nine spring-winter cereal mixture crops and six monocrop varieties were seeded to determine the forage yield and quality advantages of the mixtures. Refer to Table 30 for the complete list of mixtures and monocrops.
Seeding
Seeds were treated with Vibrance Quattro cereal seed treatment before seeding.
Seeding rate was targeted at 75% for each cereal crop in a mixture, as follows:
Barley, Oats, and Rye: 225.0 plants/m2 (20.9 plants/ft2)
Spring Triticale and Winter Wheat: 277.5 plants/m2 (25.8 plants/ft2)
The target seeding rate calculation for the small plot area was based on 1,000 kernel weight, germination, plot area and 5% mortality rate.
This project was seeded on May 27, 2022, with a 6-row Fabro Plot drill and at a seed depth of 0.75’’.
The soil temperature and moisture measured in the top 6’’ was 11.7°C and 9.0% VWC, respectively.
Fertility
Fertilizer was applied through mid-row banding and at a rate of 279 lbs/acre using dry fertilizer blend. The fertilizer rate was determined based on soil test results completed at 0-6’’ before seeding. The N, P, K, and S application rate was 72 lbs/acre, 35 lbs/acre, 27 lbs/acre, and 13 lbs/acre, respectively.
Spraying
A prepass spray was performed prior to seeding using StartUp® herbicide at a rate of 0.67 L/acre on May 20, 2022. No pre-emergence spray was carried out. In-crop spraying was performed with Prestigue XL at 0.81 L/acre on June 24, 2022.
Harvest
Time of harvest was determined based on crop development, which was when barley was at soft dough stage and oat was at late dough stage. Plots were harvested on August 8 and 16, 2022 using a forage harvester. Forage samples for each variety were sent to A&L Laboratory in Ontario for quality analysis.
Results
Forage Dry Matter Yield
Forage dry matter yield (DMY) ranged from 955-5,552 lbs/acre (Table 31). The monocrops AAC Wildfire Winter Wheat, Bobcat Triticale, and Prima Fall Rye had the lowest DMY at 955 lbs/acre, 1,899 lbs/acre, and 1,985 lbs/acre, respectively. The monocrop CDC Austenson Barley had the highest DMY at 5552 lbs/acre and was statistically significant compared to AAC Wildfire WW/CDC Austenson Barley mixture (3,375 lbs/acre) and the monocrops AAC Wildfire Winter Wheat (955 lbs/acre), Bobcat Triticale (1,899 lbs/acre) and Prima Fall Rye (1,985 lbs/acre). The second and third highest DMY was Bobcat Triticale/Taza Triticale mixture at 5524 lbs/acre and the monocrop Taza Triticale at 5235 lbs/acre but were only significantly different from AAC Wildfire Winter Wheat (955 lbs/acre), Bobcat Triticale (1899 lbs/acre), and Prima Fall Rye (1985 lbs/acre).
Crude Protein
Crude Protein content (CP) varied between the varieties (8.1-18.9%), refer to Table 31. The varieties with significantly higher CP which meet all beef cattle stock nutritional requirements were AAC Wildfire WW (18.9%), Bobcat Triticale (16.4%), and Prima Fall Rye (15.5%). Monocrop CDC Baler Oats had the lowest CP at 8.1% followed by Taza Triticale and AAC Wildfire WW/Taza Triticale mixture both at 8.3%.
Detergent Fibres
In this study, neutral detergent fibre (NDF) was significantly higher in CDC Baler Oats (48.5%) and Taza Triticale (48.3%) than AAC Wildfire Winter Wheat (38.8%) and Bobcat Triticale/CDC Austenson Barley (38.2%) but not significantly different from any other variety (Table 31). AAC Wildfire Winter Wheat (38.8%) and Bobcat Triticale/CDC Austenson Barley (38.2%) were also significantly lower in NDF than Prima Fall Rye/CDC Baler Oats (45.2%), AAC Wildfire Winter Wheat/Taza Triticale (47.2%), and Bobcat Triticale/CDC Baler Oats (47.1%). Acid detergent fibre (ADF) value is inversely related to digestibility. Bobcat Triticale/CDC Austenson Barley (19.9%) had a significantly lower ADF% than all other varieties but not significantly different from the monocrop CDC Austenson Barley (21.4%), AAC Wildfire Winter Wheat/CDC Austenson Barley (21.4%), and Prima Fall Rye/CDC Austenson Barley (22.0%). The least digestible variety, based on higher ADF content, was Taza Triticale (27.4%) but was only statistically different from Bobcat Triticale/CDC Austenson Barley (19.9%), CDC Austenson Barley (21.4%), AAC Wildfire Winter Wheat/CDC Austenson Barley (21.4%), and Prima Fall Rye/CDC Austenson Barley (22.0%).
Total Digestible Nutrients
The total digestible nutrients (TDN) is a measure of the digestible components of feed and also the energy available to the animal. Depending on the life stage of the animal, TDN is recommended to be between 55-70%. The results from this study showed that all varieties were within or exceeded this general recommendation. The varieties that exceeded the recommendation were AAC Wildfire Winter Wheat (78.9%), AAC Wildfire Winter Wheat/CDC Austenson Barley (73.6%), AAC Wildfire Winter Wheat/CDC Baler Oats (70.7%), Bobcat Triticale (74.8%), Bobcat Triticale/CDC Austenson Barley (72.7%), Bobcat Triticale/Taza Triticale (71.4%), CDC Austenson Barley (72.8%), Prima Fall Rye (79.5%), Prima Fall Rye/ CDC Austenson Barley (71.9%), and Prima Fall Rye/ CDC Baler Oats (71.1%). Prima Fall Rye monocrop was significantly higher (79.5%) in TDN than most other varieties except the monocrops AAC Wildfire Winter Wheat (78.9%) and Bobcat Triticale (74.8%).
Minerals
Mineral balance is important for animal function and growth. Results for mineral contents of seeded mixtures and monocrops are provided in Table 31. The ideal calcium (Ca):phosphorus (P) ratio should not be lower than 1.5:1. All varieties and mixtures were within this recommendation, except AAC Wildfire Winter Wheat/Taza Triticale, Bobcat Triticale/Taza Triticale, Prima Fall Rye/Taza Triticale, and Taza Triticale monocrop which were below the recommended Ca:P ratio. All treatments exceeded Ca requirements for all life stages of beef cattle, except AAC Wildfire Winter Wheat/Taza Triticale (0.22%), Prima Fall Rye/Taza Triticale (0.22%), and Taza Triticale (0.22%) monocrop which fell below minimum requirements. Only one treatment, Prima Fall Rye (0.25%), met P requirements for a dry cow. All varieties exceeded potassium (K) requirements and ranged from 1.52-3.77%. The only treatment that was within magnesium (Mg) requirements for cattle was AAC Wildfire Winter Wheat (0.22%).
Relative Feed Value
All monocrop varieties and mixtures have a relative feed value (RFV) above 100 (Table 31). Bobcat Triticale/CDC Austenson Barley had the greatest RFV at 179% and was significantly different from Prima Fall Rye/CDC Baler Oat (142%), Bobcat Triticale/CDC Baler Oat (137%), AAC Wildfire Winter Wheat/Taza Triticale (136%), Prima Fall Rye/Taza Triticale (133%), CDC Baler Oat (131%), Taza Triticale (130%).
Conclusion
Overall, the mixtures did not clearly provide a forage yield advantage over their respective monocrops. But the advantage of mixing winter and spring cereals together would be the potential of winter cereals to re-grow for fall grazing after an initial harvest (greenfeed and silage) in the summer of the main cereal crop in a spring/winter cereal mixture. The re-growth is able to provide a good amount of forage to extend the grazing season without any extra inputs in carrying the winter cereals from summer through early fall for fall grazing. Quality wise, lower forage quality was observed for spring/winter cereal mixtures resulting from ‘dilution’ of higher quality forage of winter cereals by the early maturing spring cereals. Furthermore, all mixtures and respective monocrops yielded exceedingly high forage material (< 68.0 %) in TDN. Spring-winter cereal mixtures generally had a lower mineral content compared to their respective winter cereal monocrops and beef cattle stock on them will need mineral supplementation to avoid deficiencies.
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