Research Coordinator: Dr. Akim Omokanye
Location: Fairview Research Farm
From: Peace Country Beef & Forage Association 2019 Annual Report
Annual crop mixtures particularly those involving cereals with legumes (intercropping systems) have been observed to provide several major advantages such as higher total yield, better land use efficiency, yield stability, and better utilization of light, water and nutrients as well as improved soil conservation and maintenance of soil fertility. In intercropping systems, peas are usually included in mixes to improve quality of the feed. To improve annual cereal and legume forage utilization as hay, green feed or silage and to develop supplementation programs for forage-based nutrition, it is important to know how the nutritional values of different forages match up with beef cow needs. This study was part of the regional silage variety trials in Alberta. In addition to the report presented here, results from this site and other parts of the province for the pea-cereal mixtures will also be reported in the Alberta Seed Guide (www.seed.ab.ca).
Objective
To compare the intercrops of oat, barley and spring triticale with 2 forage-pea varieties for forage yield and feed quality.
Methods
Experimental Site: Fairview Research Farm (NW-5-82-3-W6M) on RR #35, MD of Fairview.
Previous Crop: The previous crop at the site was an alfalfa hay crop for several years until the Fall of 2018.
Land Preparation: In the Fall of 2018, the site was sprayed with Roundup at 1.0 L/acre (to kill the existing alfalfa-dominated vegetation) and plowed. The site was disced & harrowed in the Spring of 2019.
Soil analysis completed in the Fall of 2018 from the soil depth of 0-6” showed an organic matter content of 8.2%, pH of 6.2 and electrical conductivity of 0.21 ds/m. The soil test reports showed 10 lbs N/acre, 14 lbs P/acre and 485 lbs K/acre as well as 9 lb S/acre.
Spring soil moisture at seeding: 12.3% (0-5 cm soil depth) and 13.6% (0-20 cm soil depth).
Spring soil temperature a Seeding: 9.48°C (0-5 cm soil depth) and 8.09°C (0-20 cm soil depth).
Experimental Design: Randomized complete block design in 4 replications with 9 intercrop treatments.
Treatments: 3 cereal monocrops (1 barley, 1 oat & 1 spring triticale) + 6 intercrops (3 cereals & 2 forage pea varieties). The forage peas used are CDC Meadow and CDC Leroy. The 9 pea-cereal mixtures (treatments) therefore consisted of the following:
1. AAC Austenson barley (monocrop)
2. Taza triticale (monocrop)
3. CDC Baler oat (monocrop)
4. CDC Austenson barley/CDC Jasper pea
5. CDC Austenson barley/CDC Meadow pea
6. Taza triticale/CDC Jasper pea
7. Taza triticale/CDC Meadow pea
8. CDC Baler oat/CDC Jasper pea
9. CDC Baler oat/CDC Meadow pea
Seeding Rates:
1. CDC Austenson barley - 300 plants/m2 (27.8 plants/ft2)
2. CDC Baler oat - 300 plants/m2 (27.8 plants/ft2)
3. Taza triticale - 370 plants/m2 (34.3 plants/ft2)
4. Pea-cereal mixtures - 75% of pea seeding rate + 50% of cereal seeding rate
Seeding date was on May 24, 2019. The seeds were sown using a Fabro plot drill equipped with disc-type openers on 9” row spacing. Six rows that were 8 m long were sown per plot. Seeding depth was 0.75”.
Fertility (actual lbs/acre): 60 lbs/acre of 11-52-0 was applied to all treatments
Spraying: Pre-emergent herbicide with StartUp (Glyphosate, 540 grams acid equivalent per litre, present as potassium salt) was applied at 0.67 L/acre. StartUp is a water soluble herbicide for non-selective weed control. In-crop herbicide application was with Prestige A (170 mL/acre) + Prestige B (800 mL/acre) for the cereal monocrops and Basagran Forte for the cereal-pea intercrops.
Harvesting for forage dry matter (DM) yield determination and quality analysis was completed on August 14 for pea-barley mixes and barley monocrop (soft-dough stage), August 15 at the milk stage of oats for pea-oat mixes and oat monocrop, and August 20 for pea-triticale mixes and triticale monocrop (late milk stage). Two composite forage samples were sent to A & L laboratory in Ontario for quality determination.
Results and Implications
Forage Dry Matter (DM) yield
The statistical analysis showed that the cereal/pea mixtures produced similar forage DM yields. However, mixtures with CDC Meadow peas seemed to have a tendency to produce higher forage DM yield than mixtures with CDC Jasper peas.
Forage Quality
Generally, all the forage quality parameters measured and reported within this trial have not been affected by cereal/pea mixtures. All the cereal/pea mixtures, as well as cereal monocrops have similar values for each forage quality parameter (Table 1).
All mixes and cereal monocrops (except for CDC Baler) seemed to have adequate CP for a dry gestating beef cow (7% CP in mid pregnancy and 9% CP in late pregnancy) and lactating beef cow (11% CP) . CDC Baler was only able to provide sufficient protein for a dry gestating beef cow, but not a lactating beef cow.
For all cereal monocrops and mixes, the forage energy as determined by total digestible nutrients (TDN) exceeded the %TDN needed by mature beef cattle (55% TDN in mid pregnancy, 60% TDN in late pregnancy and 65% TDN during lactation).
The forage Ca varied from 0.25 - 0.36%. Only the 0.18% Ca requirements of a dry gestating beef cow was met by the cereal monocrops and mixtures tested. However, all cereal monocrops and mixtures fell short of the 0.58% Ca required by a lactating beef cow.
The forage P was generally above 20%, varying from 0.20 - 0.25% P. Only the 0.16% P requirements of a dry gestating beef cow was met by the cereal monocrops and mixtures tested. However, all cereal monocrops and mixtures fell short of the 0.26% P required by a lactating beef cow.
Only CDC Austenson barley + CDC Jasper pea mixture had <1.00% K. Other mixtures and cereal monocrops had >1.00% K. None of the cereal monocrops and mixtures fell short of the amount of K needed by mature beef cattle.
The forage Na generally varied from 0.11 to 0.12%. This indicates that the requirements for Na by mature beef cattle have been met by all cereal monocrops and mixtures.
Conclusion
Intercropping refers to the simultaneous growing of at least two crop species in close proximity at (about) the same time, leading to enhanced interspecific interactions and crop diversity. Spring barley, oat and triticale monocrops and their intercrops with two forage varieties were evaluated for forage production, nutrition quality and suitability in the beef cattle diet. Sustainable management involves matching the nutritional quality of forage types with the nutrient needs of different beef cow categories. The cereal monocrops compared well with cereal-pea mixtures in every aspect as none of the parameters measured within the trial differed significantly between treatments.
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