Roundup Ready/Conventional Alfalfa Establishment Compared
Dwain W. Meyer and Robert Nudell
Roundup Ready alfalfa was originally release in the fall of 2005, but an injunction on seeding of new acres was put on in late March 2007. This experiment was seeded April 18, 2006 with the objective to evaluate establishment techniques for Roundup Ready compared with a standard conventional variety. The experiment was laid in the field using a randomized complete block with the treatments in a split-plot arrangement and four replicates. The whole plot was two alfalfa varieties, DKA34-17RR and AmeriStand 403T, and the subplot four establishment methods. The establishment methods for the conventional variety was a check with no weed control, Pursuit at 2 fl oz/acre applied at the 3rd trifoliolate leaf stage, Buctril applied at 1 pt/acre with a separate application of Select at 1 pt/acre, and a Paul oat companion crop seeded at 1,200,000 seeds/acre. The establishment methods for the Roundup Ready variety was Roundup at 0.75 lb ae/acre at the 2 to 3 trifoliolate leaf stage, Pursuit at 2 fl oz/acre, Paul oat companion crop, and a Westford barley companion crop seeded at 1,200,000 seeds/acre. The alfalfa was seeded at 10 lb/acre with a conventional double-disc-opener drill into a well-prepared seedbed at Fargo, ND. The soil type is a Fargo clay. Soil test for P and K indicated adequate levels for alfalfa establishment. Plot size was 10 by 30 feet. A rain shortly after seeding resulted in excellent emergence.
Forage yields were determined by harvesting a strip 38 inches by 25 feet with a Carter flail harvester. The first harvest was taken July 3 at 20% bloom, the second August 22 at 80% bloom, and the third October 20 when regrowth was initiating (about 2 to 3 inches in height).