Forage legumes for a cool climate

Paul Hargreaves, Jennifer Flockhart
Posted: 06.04.2022
This article considers the yield and quality of a range of alternative legume-based forages grown under cool wet temperate climate conditions in Scotland. Changing consumer expectations of farming is providing opportunities for more local and sustainable protein sourcing for livestock feed, especially in the dairy industry. We have demonstrated that crimson clover (Trifolium incarnatum), red clover (Trifolium pratens), pea (Pisum sativum), lupin (Lupinus angustifolius), pea/barley, and lupin/barley mixtures can be successfully grown in a cool wet temperate climate. Red clover was highest yielding with a similar protein content compared to the other legume options and grass-clover mixtures. Alternative forages can be grown in a cool wet climate and produce similar yield and forage protein quality, including as silage, as a typical grass white clover mixture.

Pea and barley mixture

 

Protein from alternative forages

Increasing on-farm plant protein production addresses emerging consumer expectations. Producing more high-protein forage reduces reliance on imported protein sources. This reduces the carbon footprint of the feed and reduces the impact of fluctuations in the price of imported feeds, e.g., soya from South America.

  • Demonstration plots of alternative forages were grown and harvested in a cool wet temperate climate in Scotland to support discussion with farmers and industry stakeholders.
  • Plots were sown in early May and harvested in early August.
  • Red clover, a red clover/grass mixture, lupin and a lupin/barley mixture, forage pea, a forage pea/barley mixture and crimson clover were grown in plots (3 m x 10 m) and compared with a perennial ryegrass/white clover mixture.
  • Initial measurements of dry matter (DM) showed that the pea/barley mixture produced 8 t/ha, the lupin/barley mixture provided 7.3 t/ha, compared to the ryegrass/white clover at 3.8 t/ha.
  • The red clover mixture had the highest crude protein content (17.7%) compared to the grass/white clover (16.9%) and pea (16.1%).
  • Metabolisable energy (ME) level was highest for the pea and the grass white clover (10.5 MJ/kg DM) while the red clover (10.3 g/kg DM), crimson clover (10.2 MJ/kg DM) and lupin (10.2 MJ/kg DM) were very similar.

 

 

Silage quality

Sub-samples of the fresh cut material were compressed into 3 litre plastic air-tight containers and ensiled for 5 weeks. These were then analysed for feed quality.

  • The silage analysis showed the pea, pea/barley and the lupin/barley mixtures gave the greater DM contents (g/kg).
  • The crude protein content of the lupin (19.2%) and red clover mixture (19.6%) were most similar to the ryegrass/white clover (20.8%).
  • The protein content of the crimson and red clover, at 18%, were close to the lupin (19.2%) and red clover mixture (19.6%).
  • The ME content of the lupin provided just over 10 MJ of ME/kg DM compared to the grass and white clover that provided 11 MJ of ME/kg DM.
  • The barley in pea/barley and the lupin/barley mixtures increased the metabolisable energy of the silages.

 

Blue lupin

 

Key practice points

  • Alternative forage crops can be grown successfully in a cool wet temperate climate.
  • Forage yield, protein content and metabolisable energy levels can be maintained with most of the alternative crops.
  • The grass/clover and clover swards are harvested several times through the growing season.
  • The legumes fix nitrogen that is available to subsequent crops. This has been estimated to be 150 to 250 kg N/ha for red clover compared to 80 to 100 kg N/ha for white clover.

Latest

References

Capraro, J., Duranti, M., Magni, C., Scarafoni, A. (2015). Developing lupin crop into a major and sustainable food and feed source. Proceedings of the XIV International Lupin Conference, Milan, Italy

PGRO (2017). PGRO Pulse Agronomy Guide. Processors and Growers Research Organisation, Peterborough, UK.

Young-Mathews, A. (2013). Plant guide for crimson clover (Trifolium incarnatum). USDA-Natural Resources Conservation Service, Plant Materials Center, Corvallis, OR, USA.

 

Downloads

Images

  • Pea and barley mixturePhotograph: Jennifer Flockhart
  • Table 1. Dry matter (DM), crude protein and metabolisable energy contents of the silages
  • Blue lupinPhotograph: Jennifer Flockhart

About this article 

Authors: Paul Hargreaves, Jennifer Flockhart
Publisher: Scotland’s Rural College (SRUC)

Copyright: © All rights reserved. Reproduction and dissemination for non-commercial purposes are authorised provided the source is fully acknowledged.

Acknowledgement: Legumes Translated has received funding from the European Union's Horizon 2020 research and innnovation programme under grant agreement No. 817634.
Citation: Hargreaves, P. R. and Flockhart, J., 2022. Forage legumes for a cool climate. Legume Hub. www.legumehub.eu

The content is solely the responsibility of the authors. No warranties, expressed or implied, are made with respect to the information provided. Information relating to the use of plant protection products (pesticides) must be checked against the product label or other sources of product registration information.

0 Comments