Back in April, sites were selected for "Direct Seeding Do's and Don'ts" plots near Canora and Invermay. In late May, Roundup was applied to both sites and then the sites were seeded.
At both locations, the centre section of a Flexicoil 5000 equipped with Flexicoil Stealth double shoot boots seeded the plots to canola and peas. In the first canola treatment at Canora, the canola was seeded at one half inch depth and the 235 lb of 34-17-0 fertilizer was side banded. Following germination an average of 19 plants per metre row emerged. In the second treatment, the canola was seeded at one and one half inches and the fertilizer was again, side banded. In this treatment, an average of 20 plants per metre row emerged. In the third treatment, the seed was again placed at the one and one half inch depth and all the fertilizer was seed placed. When the plant counts were done at this treatment, there was an average of less than one plant per metre row! When the seed was placed at the one half inch depth and the all the fertilizer seed placed, average emergence was 1.6 plants per metre row. The canola could forgive the deep seed placement but it couldn't forgive the seed placed fertilizer.
In the first of the pea treatments, an average of 20 plants per metre row were counted where the seed was placed at a two inch depth and the fertilizer (80 lb of 12-51-0) side banded. Plant numbers declined as seeding depth increased and the fertilizer was seed placed. As in the case of the canola, the peas just didn't care for the seed placed fertilizer in combination with a deep seeding depth. However, an average of 20 plants per row were counted in the treatment where the peas were seeded at a 2 inch depth and the fertilizer seed placed. This is consistent with research findings where some research shows there is no damage to the pea seedlings when the phosphate fertilizer is seed placed while other research shows that side banding is more beneficial to the crop.
The Invermay plot was also successful in showing the do's and don'ts of direct seeding and also how very important it is to use in-crop herbicides. We just didn't get the post emergence herbicide applied and the plot turned out to be a mess. This wasn't so great for our cooperators, but we appreciate them bearing with us. There were some interesting results demonstrated by the plot, despite the excess of weeds. For instance, where the canola was seeded at one half inch and 235 lb of 34-17-0 side banded, 22 plants per metre row emerged. Prior to mowing the plot in late July, the canola was in full flower and highly competitive with the weeds. In the second canola treatment, the canola was deep seeded and the fertilizer side banded. Only 12 plants per metre row emerged but again in late July, the crop was competitive against the weeds. In contrast, in the treatments where the fertilizer was seed placed and the canola either seeded at one half inch or at one and one half inch, you had to look very closely to find a canola plant in the row. By late July, the weeds had overtaken the treatment and we had a real mess.
Since peas are not as competitive with weeds as canola, the differences between treatments weren't quite so visually dramatic. In the treatment where the peas were inoculated, the 80 lb of 12-51-0 fertilizer side banded and the peas seeded at a depth of 2-3 inches, the average number of plants per metre row was 12. By late July, it was still possible to see the peas among the weeds. In contrast, the other treatments included seed placed fertilizer and as a result, the number of plants declined. By late July, finding the peas among the weeds was tough work.
The Invermay site is deemed successful in that it showed just how important the in-crop weed control is. No one should think that direct seeding will eliminate post emergence weed control. The field in which our plot was located at Invermay was also direct seeded but the cooperators applied post emergence herbicides. As a result, their field was clean and looked very much better than our little plot. The sites at both Invermay and Canora also showed how important proper seed depth is and how harmful high rates of seed placed fertilizer can be to the germination of crop plants.