Field notes
Reading wet-season yield gaps across small Vinh Phuc plots
How uneven bund height and staggered transplant dates show up in end-of-season bags long before anyone weighs the harvest.
When neighbouring plots share the same seed lot and still finish the wet season twenty percent apart, the story rarely lives in a single factor. In Vinh Phuc we often find the gap in bund maintenance, transplant timing, and how long water sits after heavy rain.
Start with a simple sketch: name each plot, note transplant week, and mark where water drains slowly. Walk those marks again after the first major storm. Soft spots along the bund and yellowing at the same corner across seasons are stronger signals than memory alone.
Weigh bags by plot, not by the whole farm. Even a rough area estimate turns a pile of sacks into a ranking. Farms that keep that ranking for two seasons usually spot the same weak corner before they buy more seed.
If labour is tight, measure only three reference plots thoroughly rather than guessing across twelve. A clear sample beats a complete but invented table.