Hibakujumoku
Hibakujumoku is a Japanese term for a tree that survived the atomic bombings of Hiroshima and Nagasaki in 1945. The term is from and.
Damage
The heat emitted by the explosion in Hiroshima within the first three seconds at a distance of three kilometres from the hypocenter was about 40 times greater than that from the Sun. The initial radiation level at the hypocenter was approximately 240 Gy. According to Hiroshima and Nagasaki: The Physical, Medical, and Social Effects of the Atomic Bombings, plants suffered damage only in the portions exposed above ground, while portions underground were not directly damaged.Surviving trees in Hiroshima
In 2011, the United Nations Institute for Training and Research in Hiroshima published a report and database detailing the surviving trees in that city. The closest tree, 370m from ground zero of the blast, is a Weeping Willow on the Motomachi riverbank of the Ōta River. The tree fell at the time of the bombing, but new buds sprouted from the roots. The second closest tree is a Kurogane holly 410m from the hypocenter, which burned down during the bombing, leaving only a stump, but miraculously sprouted in 1949.. In all, in 2011 there were 12 survivor trees within 1000m of the blast, and 48 within 2000m.Regeneration
The rate of regeneration differed by species. Active regeneration was shown by broad-leaved trees. Approximately 170 trees that grew in Hiroshima in 2011 had actually been there prior to the bombing. The oleander was designated the official flower of Hiroshima for its remarkable vitality.Types of ''hibakujumoku''
Hibakujumoku species are listed in the UNITAR database, shown below, combined with data from Hiroshima and Nagasaki: The Physical, Medical, and Social Effects of the Atomic Bombings. A more extensive list, including distance from the hypocenter for each tree, is available in Survivors: The A-bombed Trees of Hiroshima.Surviving trees in Nagasaki
Although not as well known as the hibakujumoku in Hiroshima, there are a number of similar survivors in the vicinity of the hypocenter in Nagasaki. Approximately 50 of these trees have been documented in English.The J-pop singer and actor Fukuyama Masaharu, who was born in Nagasaki to survivors of the atomic bomb, has been active in preserving Nagasaki's hibakujumoku. His song "Kusunoki", from his 2014 album Human, honours the camphor trees of Sannō Shrine. Fukuyama used the song to solicit donations which the city of Nagasaki used to establish the Kusunoki Foundation, dedicated to preserving the trees and teaching the history associated with them.