Apparently, the sunflowers are not doing their thing. Too bad.

TOKYO majirox news — Sunflowers are virtually ineffective in soaking up radioactive cesium from contaminated soil, the Ministry of Agriculture, Forestry and Fisheries MAFF on Sept. 14.Ministry officials carried out the tests from May in areas near the radiation-spewing Fukushima Daiichi nuclear power plant.Ministry officials said that sunflowers absorbed almost no cesium from contaminated soil.MAFF discovered that of the numerous decontamination measures it has attempted in Fukushima prefecture, removing topsoil was the most effective.

via Sunflowers ineffective in radiation decontamination | Majirox News.

Speaking of topsoil,

Professor Tomoko Nakanishi of the University of Tokyo’s Graduate School of Agriculture and Life Sciences believes the contamination is mostly superficial.

Her early studies have shown that vast majority of radioactivity is held within the top 5cm of the soil.

As a result, she believes that relatively small quantities of radioactive Caesium 134 and 137 will be absorbed into the stalks of rice, and even fewer into their grains.

“Only the surface is contaminated,” she told me, “only the first 5cm is highly contaminated.”

Professor Takanishi concedes that consumers might not be convinced by these reassurances.

“If you don’t want to eat it,” she says, “just discard this year’s product but next year I’m really optimistic. It will be safe to eat.”

But if that conclusion is proved right, there still remains the challenge of clearing up large areas of poisoned soil.

Removing the top soil is one technique but it needs to be disposed of and the work is very expensive. Ploughing it deeper into the ground can dilute it but that too is a costly option.

Six months on, much of the science is still uncertain and it may be years before farmland can be convincingly declared safe.

via Inside Japan’s Nuclear Ghost Zone | BBC