Research Coordinator: Dr. Akim Omokanye
Location: Fairview Research Farm
From: Peace Country Beef & Forage Association 2020 Annual Report
Oats are an important forage-type cereal crop in the Peace Country region. Oat variety types include: general purpose, forage, feed, and hulless oats. The economic value of cereal forage for feeding beef cattle is dependent on both its yield and feeding value (i.e., crude protein, minerals, detergent fibres, energy, digestibility and animal performance). New varieties of oats are registered on a regular basis. Every year, PCBFA tests new oat varieties as they become available along with older varieties for silage. As part of the Regional Silage Variety Trials (RSVTs), PCBFA provides scientifically sound oat variety performance information to livestock producers, industry, and extension specialists. In addition to the findings of the oat variety trial from Fairview Research Farm being presented here, the results from the RSVTs across the different trial sites in Alberta will also be reported in the Alberta Seed Guide (www.seed.ab.ca).
Objective
To identify oat varieties with superior forage yield and quality for beef cattle production, and to encourage the adoption of oat varieties with forage production potential for livestock in the Peace Country region.
Methods
Experimental Site: Fairview Research Farm (NW-5-82-3-W6M) on RR #35, MD of Fairview.
Site soil information from the surface soil (0-6” soil depth) before seeding: pH = 6.2, organic matter = 4.7% and electrical conductivity = 0.21 (dS/m).
Cropping history: Before the fall of 2018, when the site was sprayed out with Roundup at 1.0 L/acre and tilled, the previous crop was alfalfa for hay production for over 15 years.
Experimental design and treatments: A randomized complete block design was used in four replications in small plots measuring 8 m x 1.8 m.
The following 10 oat varieties were tested for silage production:
1. AC Juniper - early maturing general purpose oat variety
2. AC Morgan - later maturing milling oat, commonly used for silage or greenfeed in the Peace
3. CDC Arborg - early maturing white milling oat
4. CDC Baler - very leafy, forage oat variety
5. CDC Haymaker - later maturing forage oat variety
6. CDC Nasser - low-lignin hull with high fat content
7. CDC Seabiscuit - organic, milling oat
8. CS Camden - milling oat
9. Murphy - widely adapted forage oat
10. ORe3542M - white hulled milling oat
Pre-seed treatment: Seeds were treated with Vibrance Quattro cereal seed treatment before seeding.
Seeding rate: 300 plants/m2 (27.8 plants/ft2).
Seeding date: May 28.
Seeding depth was 0.75”.
Seeding method: Six rows were seeded using a Fabro plot drill equipped with disc-type openers on 23 cm (9 inches) row spacing.
Surface spring soil moisture and temperature at seeding from 0-5 cm soil depth were respectively 13.2% and 9.5°C.
Fertility for an average oat yield (actual lbs/acre) was applied at: 37 N + 35 P2O5 + 0 K2O + 13 S.
Spraying: Pre-emergent (StartUp glyphosate + LI surfactant); In-crop (Prestige XL at 0.71 L/acre).
Measurements taken include: Oat height, lodging, forage dry (DM) yield, and feed quality. Harvesting for forage dry matter (DM) yield determination was done on August 31st when majority of the oats were at the milk stage. Forage samples were shipped to A & L laboratory, Ontario for forage quality determination.
Results
Plant Height and Stem Lodging or Breakage
Oat varieties differed significantly with respect to plant height (Table 1). CDC Baler oat grew taller than most oats. Next to CDC Baler in plant height was CDC Haymaker, followed by CDC Nasser oats. CS Camden and AC Juniper did not grow as tall as other oats tested here in this study.
Fairview and area witnessed a strong storm on August 3. The storm was a combination of wind, rain, and hail that resulted 28.3 mm of rainfall over a short period. The storm caused severe lodging on most of the oats tested (Table 1). The most affected variety by the storm was CDC Baler oat with less than 30% standing plants after the storm, followed closely by CDC Seabiscuit, CDC Haymaker, and Murphy oats with 30 to 50% plants left standing. AC Juniper, CS Camden, and CDC Arbor were the most resistant oat varieties to plant lodging as they all had 91 to 100% erect plants following the strong storm. Morgan and CDC Nasser also exhibited some degree of standability with 76-89% erect plants after the storm.
Table 1. Lodging resistance and plant height of oats tested in 2020.
Means within a column for plant height with different letters
differ (P <.05) according to LSD. Coefficient of variation for plant height = 4.86%.
Forage Dry Matter Yield
The statistical analysis showed that forage DM yield was significant influenced by oat varieties tested. AC Juniper oat had the highest forage DM yield and it significantly out yielded the bottom 2 oats by as much as 1329-1679 lbs DM yield/acre (Figure 1). On the other hand, AC Juniper oat produced similar forage DM yield to most oat varieties tested in this study. Overall, forage DM yield varied from 6631 lbs/acre for CDC Seabiscuit oat to 8310 lbs/acre for AC Juniper oat.
In the study area, over the years, CDC Haymaker, CDC Baler, and Murphy oats have always shown greater forage production (yield) potential than what we recorded this year. Looking at Table 1, one could say that lodging had a more significant negative effect on the growth, harvestable forage, and forage DM of CDC Haymaker, CDC Baler, and Murphy, compared to the other oats tested, hence the reason for the lower forage DM yields. Lodging is an important factor limiting yield potential and reducing a farmer’s profitability. In general, lodging also makes harvesting difficult.
Forage Quality
The forage crude protein (CP) content was similar for the oat varieties tested as indicated by the statistical analysis. Forage CP varied from 10.0 to 11.8% for the oats (Figure 2). As recommended, a mature beef cow requires 7% protein in mid-pregnancy, 9% in late-pregnancy and 11% during lactation. Overall, all oats had adequate protein for a dry gestating beef cow, which needs 7 to 9% in mid- to late-pregnancy. AC Juniper, CDC Haymaker, CDC Baler, CDC Nasser, and CDC Seabiscuit oats were the only varieties that met the protein requirements of a lactating mature beef cow because they all conveniently had 11% or more CP.
The protein requirements of 12-14% CP by growing and finishing calves couldn't be met by any of the oat varieties tested here in the present study. This is expected as oats decline drastically in forage protein with advancing stage of growth from the boot stage through heading to the milk stage. Protein supplementation would always be needed when feeding oat forage (silage or greenfeed) to calves.
Forage Energy
The main measure of energy (total digestible nutrients, TDN %) for beef cattle as well as other forms of energy (net energies for lactation, growth, and maintenance, Table 2) were all statistically similar for oats tested here in the present study. However, with about 68% TDN, CDC Arborg oats showed a tendency for higher forage TDN than other oats. The forage TDN generally varied from 61.8-67.5% for the oats tested (Figure 3). All oats were able to meet the TDN requirements of a mature beef cow in mid- and late-pregnancy (55-60% TDN). For a lactating beef cow, which needs 65% during nursing, CDC Arborg, CDC Nasser, CDC Baler, and ORe3542M were the only four oats that would provide sufficient TDN for this category of beef cow in this study.
Forage Minerals
The major minerals for livestock nutrition include calcium (Ca), phosphorus (P), sodium (Na), magnesium (Mg) and potassium (K). These minerals are required at comparatively high levels in diet as percent or grams per day. The major minerals (Ca, P, K Mg, Na) and the resulting Ca:P ratios were all statistically similar for the oats tested in the present study (Table 3). Except for forage Fe content, the forage trace minerals measured were also similar for oat varieties. For the forage Fe that differed between oats, CDC Baler had significantly higher forage Fe content than other oats (expect for CDC Seabiscuit and CDC Nasser).
Overall, all oats would be able to meet the Ca, K, Mg, Na, and S requirements for a dry gestating beef cow. For a nursing beef cow, only K, Na, and S seemed to have sufficient amounts for this category of beef cow. Most oats had far lower levels of P and Cu than what mature beef cattle need. The forage oat varieties examined in the present study far exceeded the 0.06-0.08% Na that is needed by a pregnant beef cow and 0.10% Na suggested for a nursing (lactating) beef cow. Supplementation of minerals and salt would be recommended for oats, so review of the feed test reports with a ration specialist is advisable.
Conclusion
Three oats (AC Juniper, CS Camden, and CDC Arborg) produced >8000 lbs DM yield/acre and ranked higher among the 10 oats tested. The three oats also had sufficient protein and energy for a dry gestating beef cow. They also seemed to stand up far batter than most oats at harvest, so harvesting was not as difficult as those oats that lodged heavily. The three oats therefore appear to be particularly suitable for production in this area. These varieties can be added to the more proven oats that have been established in the Peace region. Because AC Juniper is an early maturing variety it can provide farmers with greater flexibility in seeding when poor weather causes delays, and may stand a better chance than other later maturing varieties to escape early-fall frost or unfavourable harvest conditions. While most minerals measured here could meet the requirements of a dry gestating beef cow, some form of mineral supplementation may still be needed when forage oats are fed to beef cattle.