On the Shonai plain in Yamagata, northern Japan — mountains on one side, sea on the other, rice in between — an ageing farming population is testing what technology can do for a crop that has been grown by hand for two thousand years. The most photographed answer is a small robot paddling through the paddies, doing the work that ducks used to do.
The duck method it is copying
Aigamo is the Japanese name for a cross between wild and domestic ducks, and the aigamo method, popularised by the farmer Takao Furuno, is a piece of organic ingenuity. A few weeks after transplanting, ducklings are released into the flooded field. They eat weeds, insects and small pests but leave the rice alone; their paddling stirs the water, oxygenates the soil and keeps it soft; their droppings fertilise the crop. No herbicide, no pesticide, and at the end of the season the grown ducks are sold for eggs and meat — a second income from the same field.
Why it needed a machine
The method is elegant and demanding. Ducks must be protected from predators, weather and disease. They have to be removed once the rice forms ears, because by then they are large enough to damage the plants. The timing, the housing and the daily care add up to exactly the kind of labour that Japan’s shrinking, greying farm workforce cannot supply. Weed control is the biggest single obstacle to organic rice, and doing it by hand or by repeated mechanical passes costs time, labour and money.
What Aigamo-Robo does
NewGreen’s robot reproduces the useful part of the duck. Dropped into the paddy and switched on, it moves through the rows stirring the water and the surface mud, which clouds the water so weed seedlings cannot get light, and keeps the soil aerated. Each unit covers about 1.5 hectares. The first version weighed about 16 kg; the second weighs around 6 kg, light enough for one person to carry between fields. It does not eat pests or lay eggs — the trade-off for a machine that never needs to be caught, fed or protected from foxes.
The Bangladesh question
Bangladesh grows more rice than almost any country on earth and, unlike Japan, has no shortage of farm labour — yet. But herbicide use has climbed steeply as wages rise and young people leave the fields, and organic rice commands a premium in Dhaka’s supermarkets that few farmers can reach because weeding without chemicals is too costly. A 6 kg robot that a co-operative could share across a village is the kind of appropriate technology that travels well, if the price does. The Japanese experience suggests the real barrier is not the engineering but the agronomy: the robot works because the paddy is flooded to a precise depth and the rows are straight, both of which are within reach of Bangladesh’s better-organised farms.
