The 2009 ASHS Annual Conference

The desert regions of the lower Colorado River Valley is home to over 300,000 acres of winter vegetables.  While most producers in the region typically produce a spring winter wheat, melon or cotton crop following winter vegetable harvest, many seek alternative cropping schemes that fit within the winter vegetable rotation.  And, although alfalfa is the single most important field crop grown along the Colorado River, many desert southwest alfalfa producers either graze sheep on slow growing alfalfa fields or let them lie inactive during the 4 month winter period.  Intercropping field peas with cereal grains for forage has great potential for winter production in the desert areas as the protein benefits of peas in pea/cereal mixtures has been shown to produce better quality silage than cereals alone in the upper Midwest and Canada.  A spring triticale variety (Companion) and 2 winter triticale varieties (Blizzard and Wintersiris) were grown in small plot trials either alone or intercropped with a forage pea (var. Mittry) to test the notion that pea/cereal intercropping may have certain advantages when grown for livestock feed.  In mixed crop treatments, peas represented an average of 22% of the seeds present at seeding.  Following the first harvest, yields of intercropped triticale/pea were not significantly different from the cereal alone, but both out yielded alfalfa grown alone during the same time frame by over 4.2 fold.  Although forage peas did not significantly enhance the Relative Forage Value (RFV) of pea/cereal mixtures, intercropping produced results that were similar to that of alfalfa alone.  The success of these intercrops seems to be highly dependent on the seeding rates for both crops.  From our preliminary results, when peas form at least 20% of the sown mixture (by weight), we found crude protein in the harvested forage to be 2 to 4 percentage points higher than with pure cereals. Acid detergent fiber (ADF) content did not vary significantly between mixtures and pure cereals, but neutral detergent fiber levels are 2 to 4.5 percentage points lower in mixtures, resulting in a higher feed intake potential.