| Introduction
Corn is a very popular silage crop in Southern Alberta for feeding cattle. The conventional way to plant corn is with a precision row crop planter. Row crop planters are dedicated, expensive and require special tractors. Another method to plant silage corn is with a conventional air drill. A project was conducted at the CACDI Lethbridge Farm to demonstrate both methods.
Materials and Methods
Silage corn was planted into tilled barley stubble at the CACDI Lethbridge Farm. The north half of the pivot #3 was planted to corn (Figure 1). The diameter of pivot #3 is 600 m (1968 ft). The total area planted to corn was 33 ac (13 ha). The area closest to the pivot center was planted with the air drill on May 15th. The area was 100 ft (30 m) wide and covered 4.5 ac (2 ha). The rest of the field was planted with the precision row crop planter on May 11th. The seeding rate for the air drill was 33,600 seeds/ac (82,990 seeds/ha). The seed spacing with the precision row crop planter was 12 in (25 mm) for a seeding rate of 32,500 seeds/ac (80,280 seeds/ha). The openers on the precision row crop planter were on a 15 in (30 cm) spacing and on the air drill were on a 9 in (23 cm) spacing. The air drill was a Flexi-coil 5000 with narrow knife openers and a fine seed roller. The precision planter was a John Deere 1780 MaxiMerge II. The corn variety was Roundup Ready 2512. The corn seed count was 2100 seeds/lb (4600 seeds/kg).
Figure 1: Pivot #3
The soil background nitrogen level was measured at 163 lb-N/ac. Nitrogen and phosphate were applied to the field at a rate of 60 and 30 lb/ac (67 and 34 kg/ha). The granular fertilizer blend was spread on the field prior to the pre-seeding tillage operation. Table 1 outlines the post emergent chemical applications to the corn field.
Table 1: Post emergent chemical applications
| Date | Operation | Rate of
Roundup (L/ac) |
| May 25 | Spot Spray | 0.5 |
| May 28 | Spot Spray | 0.5 |
| June 1 | Spot Spray | 0.5 |
| June 12 | Spot Spray | 1 |
| June 20 | Spray entire field | 1 |
.
The corn was irrigated with 17.5 in (445 mm) of water during the growing season. Rainfall was recorded at 1.6 in (40 mm) during the growing season.
The corn was harvested for silage on September 18th with a John Deere self propelled forage harvester.
Results
Establishment of the corn planted with the precision row crop planter was very good. Growth of the corn planted with the air drill was delayed. The delayed growth of the corn planted with the air drill continued until late in the growing season. There was no visual difference between the two planting methods at harvest time.
Yield samples were taken by harvesting a single pass the length of the field. The yield of the corn planted with the precision row crop planter and air drill was 19.2 ton/ac (48.2 tonne/ha) and 17.3 ton/ac (43.4 tonne/ha), respectivel
Discussion and Conclusion
The corn planted with the air drill was planted deep due to dry soil at planting time. This deep planting depth caused the delayed growth and decreased yield of the corn planted with the air drill. The uneven plant spacing of the corn in the rows also contributed to the decreased yield of the air drill planted corn.
Flexi-coil, the manufacturer of the air drill, offers a segmented roller for seeding corn. The roller has a narrow fluted area. This causes the roller to turn faster resulting in more evenly spaced seeds. The segmented roller should be used in future demonstrations.
Acknowledgements
Monsanto provided a portion of the post emergent chemicals for the project. M & R Farms seeded the corn with the precision planter. The Agricultural Technology Centre (ATC) tilled the field, seeded the corn with the air drill and sprayed the crop. Dave Duban harvested the corn.
This report is published under the authority of the minister of Agriculture for the Province of Alberta and may not be reproduced in whole or in part without the prior approval of the AgTech Centre. |