Were direct seeders with standing stubble and heavy residue worried on May 1 because of the late wet spring we were having? Two direct seeders featured in this article were confident they could mange this kind of this wet spring as well or better than conventional farmers. Garry Meier and Kelvin Grisdale both farming in northeastern Saskatchewan felt they had the flexibility in their systems to handle these conditions.
Kelvin farms black, medium to heavy clay soils with his father and uncle close to Weekes. They seed into standing stubble using a Flexi-coil 5000 air-drill. However, they do band anhydrous in the fall so Kelvin feels that the small amount of soil disturbance this operation creates will help to dry out the soil enough on a wet spring so they can seed. He says if it is dry enough for my neighbors to cultivate then I expect to be seeding. He did have a couple of fields that he didn't band anhydrous into the previous fall and he felt they might be a test for their system. However, he says he still had the flexibility to cultivate those fields to dry them out if he had to.
A number of direct seeders in the northeast feel it is important to do aggressive harrowing in the fall to reduce residue loads and even create a bit of soil disturbance. Many others are getting the benefits of direct seeding even though they are using a "two pass" system. The first pass is a low disturbance fertilizer banding operation frequently placing anhydrous ammonia. If conditions are favorable this pass is done in the fall. Roundup is usually applied just before a single low disturbance seeding pass is made in the spring. This system normally leaves a significant portion of the stubble still standing after seeding. Even though it means the expense of an extra trip over the field these producers feel extra soil disturbance is needed to warm and dry their fields out.
Garry and Glen Meier direct seed on gray wooded clay soils at Ridgedale. Garry is well known in direct seeding circles around Saskatchewan. He says direct seeders probably have more options to accommodate wet seeding conditions than conventional farmers. He and his brother Glen have developed a single pass seeding system they use to seed into soils so wet they have difficulty traveling on them with their two wheel drive spray coupe. In 1994 they gave their system a good test. Their seeding was interrupted by late May rains. They observed that they were able to seed as soon as, or quite often sooner, than their neighbours who tilled their land that spring.
Here is what they have done to made their system work: Gary says, "Seed as shallow as possible to moisture. Just scuff it in." He points out that seeding shallow reduces draft which reduces rutting and compaction from tractor slippage.
Second, reduce footprint pressure from implements and tractor tires. Gary says the biggest problem they had seeding in wet conditions last year was the tire tracks that the dealer's 1000 gal anhydrous tank left. (The tank trails behind the air seeder.) By moving axles and increasing tire size they have gotten the footprint pressure on the ammonia tank equivalent to the tractor. They pull their forty-eight foot air seeder with a four wheel drive with triples without extra ballast giving a ground pressure of 9 psi. on the tractor.
Third, be very cautious about over packing the soil in the seed trench particularly on heavier soils. Garry says in very wet soils you need just enough pressure to form a trench over the seed. The importance of this trench is to reduce the depth of soil over the seed. If you over pack, especially in clay soils, you will get a smearing action over top the seed row that will bake, causing the seed row to dry out. This can exclude oxygen from the seed row which is essential for germination of all crops and nitrogen fixation by pulse crops. Meiers use a quick change mounted packer system. They adjust packing pressure by changing spring pressures.
Garry thinks that if your implement has fixed packing pressure you might try using openers that leave a narrower trench than the width of your packer wheel. Your packing wheel rides up on the shoulders of the trench and reduces actual packing pressure over top the seed.
Direct seeders do have options to help them deal with high soil moisture conditions. A word of caution if you want to dry out high residue stubble by cultivating it with full cut sweeps. You will probably need to make several passes with harrows to level out the piles of straw. You might be better off to do your best at seeding it in one pass.