Cropping Systems Including Pea and Lentil and Livestock for Sustainable Production in Central Montana, USA.

Cropping system profitability and sustainability largely determines the success of pea and lentil industry. This study investigated the yield and economical return of six crop rotations in central Montana in 2007 and 2008. Specifically, winter wheat was grown following (1) winter pea grown for hay, (2) spring pea grown for grain, (3) winter lentil grown for green manure, (4) winter lentil grown for grain, in comparison with the traditional winter wheat (5) following summer fallow or (6) following spring wheat. Different amounts of nitrogen were applied to wheat only. Average yields for the 6 systems were: (1) 2076 kgha^-1 of pea hay +1842 kgha^-1 of winter wheat, (2) 999 kgha^-1 of pea grain + 1551 kgha^-1 of winter wheat, (3) 1351 kgha^-1 of winter lentil green manure + 1993 kgha^-1 of winter wheat, (4) 1025 kgha^-1 of lentil grain +1598 kgha^-1 of winter wheat, (5) 2146 kgha^-1 of winter wheat, and (6) 1244 kgha^-1 of spring wheat + 1034 kg ha^-1 of winter wheat. Based on the prices of 2007 and 2008, the winter wheat rotated with pulse crops generated more net returns than following summer fallow or spring wheat. The greatest net returns were generated when optimum nitrogen was applied to winter and spring wheat at 45 to 67 kgN ha^-1.  Without nitrogen input (0N), winter wheat following pea and lentil for hay or grain resulted in greater net returns than that following spring wheat. Organic farming using winter lentil and pea for green manure or cattle grazing was also discussed.