IRRI agronomy challenge: seeding isn't that easy
January 7: We tried the drum seeder, but it quickly sunk to the axle in deep mud. This is a special kinda dirt!
Achim Dobermann and Leigh Vial realize that broadcasting is going to work better than drum seeding.
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We tried larger diameter wheels to keep the metering drums out of the mud, but alas no help. We even tried to lift the seeder a little by pulling the tow-bar a little higher than normal (logical for a six-foot-something German), but this helped little and was leading us both straight to a physiotherapist if we persisted. We learnt that the drum seeder is not applicable to all situations.
Plan B was broadcasting at 80 kg/ha. After a calibration run (scales stolen from Achim’s kitchen like all good farmers do...), we both got our rates about right, but getting a uniform spread is a little bit of an art. The shoots are quite long now, which may help where the water is lying. It took two of us about 30 minutes to broadcast the 0.25 ha; slow, but heaps quicker than transplanting.
We spent the last hour carving extra ditches to drain the field, as removing the last centimetre of water is tough. Gravity offers little at this point. I dearly wish we could design for a small slope across the field – say 0.1% or more - to convince the water to go somewhere with conviction. With a laser it may be possible next time, but maybe in this system this slope would disappear too quickly.
January 8: Praying for dry weather... I am sitting here listening to MORE rain on the roof and my heart is sinking. I can see why breeding for a seed that happily germinates and grows from under an inch or two of water makes real sense! The drains are doing admirably in getting water off the field, but deep in my cockles I fear a failure.
January 9: Maybe not...it is touch and go, but I see a few pale shoots emerging from shallow puddles. We will press on and apply butachlor at 1.7 L/ha this afternoon, then snail control once conditions permit.