While discussing forages one day with Florian Balawyder and Grant Peterson of Preeceville and Ernie Patrick, Extension Agrologist, the conversation turned to establishing alfalfa. With the registration of Pursuit on seedling alfalfa, many producers are now intercropping alfalfa and Pursuit Smart canola. This practice allows them to establish a stand of alfalfa and take off a cash crop in the year of establishment. But does the competition from the canola affect the vigour of the alfalfa stand? We decided a demonstration might answer some of the questions.
A number of objectives for the demonstration were set out. The first was to direct seed the plot. The second was to show the effectiveness of Pursuit on alfalfa seedlings. The effect of different canola seeding rates was the third. Determining the vigour of the stand in the various treatments in years 1 & 2 were the fourth.
Grant Peterson's field just south of Preeceville is where the site is located. The site was sprayed on May 22 with 1.0 l/ac Roundup to control volunteers and winter annuals. Seeding into standing barley stubble occurred May 28 using a Conserva Pak with 12 inch row spacings.
In all treatments, 50 lbs of N and 36 lbs P205 were side banded. Alfalfa was seeded at 6 lbs/ac across the treatments.
No canola was seeded in Treatment #1. In Treatment #2, the canola-seeding rate was 4 lbs/ac. It was 5.5 lbs/ac in Treatment #3 and 8 lbs/ac in Treatment #4.
A mix of Pursuit and Poast (with a little Merge) was applied to the plot June 30 to control wild oats, green foxtail and stinkweed.
On September 4 the plot was evaluated. In Treatment #1, the alfalfa plants were thriving. They had a lush green colour and were 8-10 inches high.
In Treatment #2, the density of the alfalfa wasn't as great but the plants appeared to be doing well. They were about 6-8 inches high. In Treatments # 3 & 4, the alfalfa plants were rather straggly in comparison to the first 2 treatments. Some alfalfa was just beginning to germinate while the taller plants were about 3-4 inches tall.
At this point, no conclusions can be drawn about the effect of the canola on the stand. While the alfalfa that had no cover crop certainly appears to be hardier than the other treatments, the alfalfa in the other treatments may very well catch up to it in year 2. Monitoring will continue through year 2. As well, while no crop would have been harvested in the establishment year in Treatment #1, a crop would have been taken off in the other treatments, which in theory would have provided some income.
Sponsorship for this project was provided by Bal Com Seeds, Cyanamid, Monsanto and Preeceville Implements.