Benefits of mixing timothy with alfalfa for forage yield, nutritive value, and weed suppression in northern environments

Abstract

Bélanger, G., Castonguay, Y. and Lajeunesse, J. 2014. Benefits of mixing timothy with alfalfa for forage yield, nutritive value, and weed suppression in northern environments. Can. J. Plant Sci. 94: 51–60. Alfalfa can be grown alone or with a grass, but little information exists on the benefits of mixing alfalfa (Medicago sativa L.) with a grass in northern environments. Our objectives were (1) to determine the benefits in terms of forage yield, nutritive value, and weed suppression of mixing timothy (Phleum pratense L.) with alfalfa and (2) to evaluate the persistence of alfalfa cultivars of varied adaptation to cold and of alfalfa populations selectively improved for superior freezing tolerance in a grass–legume mixture and in monoculture. This study was conducted in a region with 1700 degree-days (5°C basis) with one harvest in the seeding year (2008), three harvests in each of two post-seeding years, and one harvest in the third post-seeding year. Adding timothy to alfalfa increased the seasonal total dry matter (DM) yield by an average of 0.57 Mg DM ha−1 yr−1 in the first 2 post-seeding years and this seasonal effect was due mostly to a DM yield increase at the first harvest. The weed contribution to total DM yield in the three harvests of the first 2 post-seeding years was greater in the alfalfa monoculture (16 to 47%) than in the alfalfa–timothy mixture (12 to 36%). Mixing timothy with alfalfa also increased neutral detergent fibre concentration and digestibility, decreased N concentration, and tended to increase water soluble concentration, but had little effect on forage DM digestibility. Cultivars and populations recurrently selected for superior freezing tolerance did not differ in persistence and had a limited effect on DM yield and nutritive value attributes. The positive effect on DM yield of mixing timothy with alfalfa was not accompanied by a reduction in forage digestibility that is usually observed with increased DM yield.

Yield and nutritive value of binary legume-grass mixtures under grazing or frequent cutting

“…Legume-grass mixtures generally provide more consistent forage yield across a wide range of environments than grass or legume monocultures (Sleugh et al 2000;Bélanger et al 2014). Legume-grass mixtures have also been shown to reduce weed invasion compared with monocultures (Tracy and Sanderson 2004;Picasso et al 2008;Frankow-Lindberg et al 2009;Sanderson et al 2012;Finn et al 2013;Bélanger et al 2014).…”

“…Legume-grass mixtures have also been shown to reduce weed invasion compared with monocultures (Tracy and Sanderson 2004;Picasso et al 2008;Frankow-Lindberg et al 2009;Sanderson et al 2012;Finn et al 2013;Bélanger et al 2014).…”

Effect of applied cultivation technology and environmental conditions on lucerne farm yield in the Central Europe

“…From all management methods, only lucernegrass mixture significantly increased forage yield in accordance with the positive effect of mixture to dry matter yield (Bélanger et al 2014). Grass legume mixtures also resist weed invasion better than monocultures (Sanderson et al 2012), however some changes in forage nutritive value could be also observed (Bélanger et al 2014). In the Czech Republic, this technology is more applied in more humid regions (CR 5: 7.5°C, 600 mm; CR 7: 6.5°C, 700 mm) which are more favourable for grass components.…”

“…These farms also harvested lucerne at the bud stage which is in line with the best forage quality declared (Hakl et al 2010, Testa et al 2011. From all management methods, only lucernegrass mixture significantly increased forage yield in accordance with the positive effect of mixture to dry matter yield (Bélanger et al 2014). Grass legume mixtures also resist weed invasion better than monocultures (Sanderson et al 2012), however some changes in forage nutritive value could be also observed (Bélanger et al 2014).…”

“…For forage legume crops such as lucerne, this point seems not important due to potential of nitrogen fixation (Carlsson and Huss-Danell 2003). The impact of applied technology on lucerne or lucerne-based stand yield was usually investigated under field plot experiment covering large area from advantages of lucerne grass mixture (Bélanger et al 2014), stand establishment (Norton and Koetz 2013), and population density (Lamb et al 2003) to applied harvest management (Hakl et al 2010, Testa et al 2011) in relation to ethanol (Lamb et al 2014) or biogas production (Hakl et al 2012). However relationships among technology, environment condition and yield were not directly investigated, because these studies were usually conducted in one or few sites, under a few treatments with limited explanation power regarding to interaction with environment as well as other technological factor.…”