The plow is a harrow, or as it's known around here a "JoHar" plow. I have one over at the old barn. They are still used with horses.
The sack is seed with a small board in it. The bag is burlap. The board holds the bag open so seed can be grabbed easily.
Shoving your hand into the bag all day, for one handful of seed at the time... The burlap will scrub the hide off the back of your hand, very rough surface.
The board in the bag reduces this friction by holding it open. The technique is to slide your hand down the board, grab a hand full of seed then pull your hand back out. A very smooth board is usually kept in the barn, we used to have one for this purpose. Used when seeding...
The Johar has dozens of short metal spikes, the angle they enter the soil is adjustable.
In this case the spike angle is small, just enough to cover the seed she sows.
Edit a newer pic of the JoHar, the upright levers are for the adjustment of the angle of the spikes into the ground.
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