43,780 Bq/Kg of cesium was measured from the ash of firewood. This firewood was taken from a mountain and left in a yard of a house in Nihonmatsu shi Fukushima.
A citizen in Nihonmatsu shi asked the ministry of the environment if they can use the firewood. As they tested it to burn, they measured 43,780 Bq/Kg of cesium on 11/23/2011. It is beyond the limit of 8,000 Bq/Kg which they can treat as normal garbage.
From the sample they burnt on 11/22/2011, they measured 28,660 Bq/Kg of cesium.
From the wood of zelkova, they measured 4,395 Bq/Kg of cesium. Apart from the skin, it was 103.8 Bq/Kg.
In November of 2011, Forestry agency banned to sell firewood which contains more than 40 Bq/Kg, but woods taken from a mountain were out of the restriction. Ministry of the environment announced not to sprinkle the ash in garden or farm to 8 prefectures in Kanto and North Japan.