Effect of Increasing Seeding Rates of Tall Fescue, Meadow Fescue, & Orchardgrass in Binary Mixtures with Alfalfa on the Yield & Neutral Detergent Fiber of the Forage Mixture.

We evaluated seeding rates for binary mixtures of tall fescue (Festuca arundinacea), meadow fescue (Festuca pratensis), and orchardgrass (Dactylis glomerata) with alfalfa (Medicago sativa) by quantifying neutral detergent fiber (NDF) & yield. This experiment was conducted from 2009 to 2011 at three sites, UW Arlington, Lancaster, and Marshfield Research Stations, seeding each grass at 0%, 15%, 30%, 45%, 60%, & 75% of alfalfa on a seed count basis. Arlington was seeded in 2009, while Lancaster and Marshfield were seeded in 2010. NDF content significantly increased as grass seeding rate increased at Arlington in 2009 (300 to 363 g NDF kg-1 DM) & in 2010 (402 to 454 g NDF kg-1 DM), at Lancaster in 2010 (377 to 440 g NDF kg-1 DM), & at Marshfield in 2010 (418 to 485 g NDF kg-1 DM). Species affected NDF content at Lancaster (377, 414, & 417 g NDF kg-1 DM for meadow fescue, orchardgrass, tall fescue respectively) and Arlington in 2010 (402, 435, & 416 g NDF kg-1 DM for meadow fescue, orchardgrass, tall fescue respectively), but not at Marshfield in 2010. At Arlington in 2009 NDF content was statistically higher for tall fescue than meadow fescue & orchardgrass (322, 300, & 303 g NDF kg-1 DM respectively). Total yields at the Arlington site were 5880 and 16423 kg ha-1in the 2009 and 2010, respectively. At Lancaster in 2010 total yields were affected by grass species, 5030, 5768, & 6533 kg ha-1 for meadow fescue, orchardgrass, & tall fescue respectively. At Marshfield in 2010 total yields were significantly higher at the 15% (9693 kg ha-1) and 60% (9882 kg ha-1) seeding rates compared to 0% (8732 kg ha-1) grass.