Forage Potential of Intercropping Barley with Faba Bean, Lupin, or Field Pea

Annual cool‐season grain legumes grown in mixtures with barley ( Hordeum vulgare L.), may offer advantages over barley sole crops for forage production. Our objective was to evaluate the effects of intercropping ‘Snowbird’ tannin‐free faba bean ( Vicia faba L.), ‘Arabella’ narrow‐leafed lupin ( Lupinus angustifolius L.), and ‘Cutlass’ field pea ( Pisum sativum L.), along with legume planting densities (LPD) on forage yields, nutritive value, and economic returns. Field studies were conducted at three sites in the Parkland region of Alberta, Canada, in 2004 and 2005. Each legume was planted at 0.5, 1.0, 1.5, and 2.0× their recommended sole crop planting density with ‘Niobe’ barley at 0.25× the recommended sole crop planting density. A barley sole crop was also included for comparison. Increasing the LPD from 0.5 to 2.0× did not effect forage dry matter (DM) but it increased the proportion of legume in the forage DM from 39 to 63%, protein concentration from 119 to 132 g kg −1 , and acid detergent lignin (ADL) from 36 to 42 g kg −1 while it decreased neutral detergent fiber (NDF) from 465 to 422 g kg −1 . Faba bean–barley, lupin–barley, and pea–barley intercrops had 64, 27, and 55% higher protein yields, respectively, compared to sole crop barley. Faba bean–barley and lupin–barley had similar forage DM yields which were 1.5 Mg ha −1 and 1.3 Mg ha −1 less than pea–barley and sole barley crops, respectively. Intercrops of Cutlass pea and Niobe barley offered the most favorable combination of forage DM yields, nutritive value, and economic returns.