AS  Vol.12 No.4 , April 2021
Harvest Time and Fertility Effects on Yield and Quality of Forage from Alfalfa, Hybrid Bromegrass and Their Mixture
Abstract: A field experiment with 24 treatments consisting of three perennial forage crops [alfalfa (Medicago sativa L. cv. AC Longview), hybrid bromegrass (Bromus riparius Rehm & Bromus inermis Leyss. cv. AC Success) and their mixture], four Cut 1 dates (approximately June 20, July 10, July 30 or August 20), and two fertilizer levels (unfertilized and fertilized) was established in late May 2014, on a Black Chernozem [Udic Boroll] silty clay soil. Forage dry matter yield [DMY], and concentration (g·kg−1 DM) of crude protein [CP], total digestible nutrients [TDN] and acid detergent fiber [ADF] data were collected over 3 years from 2015 to 2017. The fertilizer treatments were imposed in 2016 and 2017. Forage crops were initially cut at four Cut 1 dates, and again cut [Cut 2] in autumn (September 2 in 2015, November 7 in 2016 and October 5 in 2017). For all three forage crops, forage DMY usually increased when Cut 1 was delayed. Delaying Cut 1 reduced forage DMY for Cut 2. Total DMY (Cut 1 + Cut 2) for all three forage crops was highest from the combination of July 10 and late Autumn cuts. Alfalfa-bromegrass mixture produced higher DMY than bromegrass or alfalfa alone. Fertilizer application resulted in a significant increase in Cut 1 and total DMY for bromegrass. The CP concentration in Cut 1 forage usually declined as the forage crops matured. The CP concentration was highest for alfalfa, followed by alfalfa-bromegrass mixture, and much lower for bromegrass. There was little or no effect of forage crop maturity on the TDN and ADF concentrations in forage. The TDN concentration was higher and ADF concentration was lower in forage from alfalfa or alfalfa-bromegrass mixture than bromegrass. Fertilizer application significantly increased CP concentration for alfalfa-bromegrass mixture. Delaying harvesting for Cut 1 increased ADF yield and TDN yield until Late July, but CP yield generally decreased with crop maturity. The ADF yield and TDN yield were higher for alfalfa-bromegrass mixture than bromegrass or alfalfa alone, and CP yield was similar for alfalfa and alfalfa-bromegrass mixture but considerably higher than bromegrass. Fertilizer application increased CP yield and ADF yield for bromegrass and alfalfa-bromegrass mixture, and TDN yield only for bromegrass. In conclusion, total DMY (Cut 1 + Cut 2) was highest for a combination of Early July and Autumn cuts. Forage yield was highest for alfalfa-bromegrass mixture, followed by alfalfa and lowest for bromegrass. The CP and TDN concentrations were higher, and ADF concentrations were lower in forage from alfalfa or alfalfa-bromegrass mixture than bromegrass.
Cite this paper: Foster, A. , Biligetu, B. , Malhi, S. , Gill, K. , Mollison, B. and Leach, D. (2021) Harvest Time and Fertility Effects on Yield and Quality of Forage from Alfalfa, Hybrid Bromegrass and Their Mixture. Agricultural Sciences, 12, 325-338. doi: 10.4236/as.2021.124021.

[1]   McElgunn, J.D., Heinrichs, D.H. and Ashford, R. (1972) Effects of Initial Harvest Date on Productivity and Persistence of Alfalfa and Bromegrass. Canadian Journal of Plant Science, 52, 801-804.

[2]   Malhi, S.S., Foster, A. and Gill, K.S. (2003) Harvest Time and N Fertilizer Effects on Forage Yield and Quality of Quackgrass (Elytrigia repens L.) in Northeastern Saskatchewan. Canadian Journal of Plant Science, 83, 779-784.

[3]   Aasen, A. and Bjorge, M. (2009) Alberta Forage Manual. Alberta Agriculture and Rural Development Publication, Agdex 120/20-1, 348.

[4]   Jenson, K.R., Joseph, G., Rigby, C. and Waldron, B. (2017) Comparative Trends in Forage Nutritional Quality across the Growing Season in Thirteen Grasses. Canadian Journal of Plant Science, 97, 72-82.

[5]   Bonin, S.G. and Tomlin, D.C. (1968) Effects of Nitrogen on Herbage Yields of Timothy Harvested at Various Stages. Canadian Journal of Plant Science, 48, 501-509.

[6]   Saskatchewan Forage Production Guide.

[7]   Yu, P., Christensen, D.A., McKinnon, J.J. and Market, J.D. (2003) Effect of Variety and Maturity on Chemical Composition, Carbohydrate and Protein Subfractions, in Vitro Rumen Degradability and Energy Values of Timothy and Alfalfa. Canadian Journal of Animal Science, 83, 279-290.

[8]   Cornell Cooperative Extension (2020) 1st Cutting Forage Quality Update. Central New York Dairy, Livestock and Field Crops, Cornell University, Ithaca.

[9]   Loeppky, H.A., Hiltz, M.R., Bittman, S. and Frick, B. (1996) Seasonal Changes in Yield and Nutritional Quality of Cicer Milkvetch and Alfalfa in Northeastern Saskatchewan. Canadian Journal of Plant Science, 76, 441-446.

[10]   Norton, N.A., Clark, R.T., Reece, P.E. and Eskridge, K.M. (2013) Quality as a Factor in the Optimal Choice of Fertilizer and Harvest Date of Meadow Hay. Journal of Production Agriculture, 10, 551-556.

[11]   Association of Official Analytical Chemists (AOAC) (1995) Protein (Crude) in Animal Feed. Combustion Method (990.03). Official Methods of Analysis, 16th Edition, AOAC, Washington DC.

[12]   Association of Official Analytical Chemists (AOAC) (1990) Fat (Crude) or Ether Extract in Animal Feed (920.39). Official Methods of Analysis, 15th Edition, AOAC, Washington DC.

[13]   NFTA (1993) Neutral Detergent Fiber Determination after Digestion of Samples in Neutral Detergent Solution with Labconco Digestion Unit. Labconco, Kansas City.

[14]   SAS Institute Inc. (2004) Online Documentation for SAS, Version 8. Cary.

[15]   Austenson, H.M. (1963) Influence of Time of Harvest on Yield of Dry Matter and Predicted Digestibility of Four Forage Grasses. Agronomy Journal, 2, 149-153.

[16]   Waldie, O., Wright, S.B. and Cohen, R.D.H. (1983) The Effects of Advancing Maturity on Crude Protein and Digestibility of Meadow Foxtail (Alopecurus pratensis) and Timothy (Phleum pretense). Canadian Journal of Plant Science, 63, 1083-1085.

[17]   National Research Council (NRC) (2000) Nutrient Requirements of Beef Cattle. 7th Rev. Edition, The National Academies Press, Washington DC.

[18]   Foster, A., Vera, C.L., Malhi, S.S. and Clarke, F.R. (2014) Forage Yield of Simple and Complex Grass-Legume Mixtures under Two Management Strategies. Canadian Journal of Plant Science, 94, 41-50.

[19]   Malhi, S.S., Zentner, R.P. and Heier, K. (2002) Effectiveness of Alfalfa in Reducing Fertilizer N Input for Optimum Forage Yield, Protein Concentration, Returns and Energy Performance of Bromegrass Alfalfa Mixtures. Nutrient Cycling in Agroecosystems, 62, 219-227.

[20]   Berdahl, J.D., Karn, J.F. and Hendrickson, J.R. (2004) Nutritive Quality of Cool-Season Grass Monocultures and Binary Grass-Alfalfa Mixtures at Late Harvest. Agronomy Journal, 96, 951-955.