Impact Objectives • Study the Hibakujumoku, or A-bombed trees, that survived the atomic bombings of Hiroshima and Nagasaki in 1945

• Discover the mechanism of an inclination in the A-bombed trees

• Promote recognition of, and information exchange about, the A-bombed trees

Towards Ground Zero

Professor Emeritus Masakazu Suzuki from the University of Tsukuba, Professor Yoichi Kunii from Tokyo University of Agriculture, and Associate Professor Hirotsugu Kanno from Meiji University, outline their work on ‘Hibakujumoku’ trees damaged during the atom bomb blasts at Hiroshima and Nagasaki wanted to pursue this further. Suzuki has been buildings and development, like Japan. Both my mentor since I was a student, so I felt that the A-bombed trees and trees damaged in it was fate that led me to this project. wars leave clear historical traces. As there are fewer and fewer people who can talk You have been studying the Hibakujumoku, about their war-time experiences, I think it is

Professor Emeritus Professor Associate Professor or A-bombed trees, that survived the atomic important to preserve these valuable trees. Masakazu Suzuki Yoichi Kunii Hirotsugu Kanno bombings of Hiroshima and Nagasaki in 1945. Why does this topic interest you and what are You are now focusing on discovering the What inspired you to become involved in this you hoping to learn? biological elucidation of the mechanism of an project? inclination in the A-bombed trees. Why is this MS: When I started my research, I knew important to understand? MS: I studied landscaping at the University that there was almost no research on of Tokyo, Faculty of Agriculture, and, after A-bombed trees because, during the Japanese MS: The phenomenon of tree inclination is graduating, I worked as a landscape designer. I occupation, press reports related to the common to trees that have suffered damage taught environmental design at the University atomic bombing were regulated by GHQ. due to fires, earthquakes and air strikes. of Tsukuba Faculty of Art and Design until I I feel that more than just studying plants However, the inclination of the A-bombed retired three years ago. However, my research scientifically, this is a complex theme that trees towards Ground Zero has been shown on A-bombed trees is ongoing in my role as needs to address other relevant subjects, to be statistically significant and is known as Emeritus Professor. This project stems from including social issues. centripetal phenomenon. However, I do not a 2009 visit to Hiroshima in which I saw an intend to pursue the biological causes in more A-bombed ginkgo biloba tree. I noticed that If there is anything that the people need to detail because we do not want to see any more affected trees were tilted towards Ground learn from the A-bombed trees, what would trees deliberately damaged. Zero. it be? KY: I would like to conduct a high precision KY: I am a professor in the Department of KY: It is very important to tell people about survey to measure the direction and angle of Landscape Architecture Science at Tokyo the damage incurred during the 1945 atomic each A-bombed trees. If it turns out, that it University of Agriculture and my current bombing. However, the ageing of the is indeed inclined towards the Ground Zero, research centres on the application of geo- victims makes it difficult to disseminate the then it means that the damage caused by the informatics technology, particularly UAV information from one person to another. atomic bomb has greatly affected the growth photogrammetry and laser measurement Therefore, I think that the A - bombed trees, as of the trees. techniques applied in landscape architectural part of our living heritage, have a role to relay fields such as historical heritage and Japanese the story to the future generations. HK: Just as A-bombed trees lean in the gardens. direction of Ground Zero, clues about the HK: The cities carry the history of their direction and strength of air strikes can HK: One of the research themes I worked on development, and also the negative history be gained through examining war-damaged during my PhD focused on trees damaged of wars and disasters. However, the negative trees. in the war. I found this very interesting, so I traces quickly disappear in areas with strong

www.impact.pub 45 From war to peace

Researchers in Japan have observed the long-term effect of damage caused by the 1945 atom bomb detonations on trees in Hiroshima and Nagasaki and seek to inform the public about the value of these survivors

Japan is the only country that has been Suzuki leads a team that seeks to inform the of the A-bombed tree message and label; attacked by nuclear weapons, having been hit general public about the existence and key and Tetsuya Sera of The Hiroshima Botanical twice – at Hiroshima and Nagasaki – in the characteristics of these remarkable trees. Garden, which helps preserve the seeds of 1945 bombing during World War II. He is keen to garner support to ensure the A-bombed trees. Recently, significant 75 years later, the two cities appear as the conservation of the trees as well as information has been obtained from Shotaro successful as any city unaffected by bombing promoting them as a living national asset Okuno of the Nagasaki Atomic Bomb as reconstruction and developments have and reminder of the atrocities of nuclear Museum. Professor Yoichi Kunii, from Tokyo erased the scars left by these devastating weapons. University of Agriculture, specialises in the events. The remaining human A-bomb application of geo-informatics technology, survivors are ageing, and numbers decline A TEAM APPROACH which he uses these techniques in landscape year-by-year, leaving fewer living reminders of Suzuki has been working closely with a architectural applications in Japanese the misery of nuclear weapons. number of collaborators who have played gardens, parks and heritage areas. This key roles in the project. Dr Nagisa Owaki, year, the student of Kunii Rihito Kumazaki However, scattered throughout the two cities, who was a student of Suzuki’s, continued obtained a degree in tree measurement stark living survivors of the two blasts rise, on her Bachelor’s, Master’s and Doctoral technology and applied it to A-bombed trees. each marked by the bombs. The A-bombed degree under the theme of A-Bombed Tree. Based at Meiji University, Associate Professor trees, which represent a variety of species, He points out that the following had also Hirotsugu Kanno’s key interests lie in provide a living reminder of the catastrophic been very helpful since the beginning of the landscape design and urban planning and he events as their trunks lean towards Ground research, partners through the Green Legacy has a special interest in war-damaged trees. Zero. Professor Emeritus Masakazu Suzuki, Hiroshima campaign: Chikara Horiguhi, Dr Takayo Negishi, from Chiba University, from the Faculty of Art and Design at the the tree doctor, among the first to diagnose focuses her research primarily on trees University of Tsukuba, notes that while many and treat the A-bombed trees in Hiroshima; affected by war. visitors and denizens of the two cities go Tomoko Watanabe of ANT-Hiroshima about their days unaware of the existence of and Nassrine Azimi of UNITAR, who Following Suzuki’s observation that many these trees, there are 160 trees in Hiroshima distribute the seedlings of A-bombed trees A-bombed trees tilted in a certain direction, and approximately 30 in Nagasaki within a worldwide; Akio Nishikiori, an architect who he and his colleagues conducted an extensive three-kilometre radius of Ground Zero. spearheaded the design and dissemination survey of the trees. They identified and measured the direction and gradient of the lean of the tree trunks as well as the deviation between tilt direction and Ground Zero. ‘Among the A-bombed trees that have been surveyed so far, those that are found within the 2km radius from Ground Zero were inclined towards it with extremely high accuracy,’ declares Kunii. His expertise in laser measurement proved invaluable in taking these measurements. ‘With the cooperation of Professor Kunii, it was possible to obtain a precise measurement using a 3D laser scanner,’ highlights Suzuki. Kunii himself believes that this technology, originally developed for civil engineering applications, would prove invaluable for use with plants. ‘I believe that the challenge of surveying the trees in this research is very valuable in the field of landscaping,’ says A-bombed Cinnamomum Camphora at Fuchi Shrine, Nagasaki City. Left side of photo is direction of Kunii. Ground zero.

46 www.impact.pub The phenomenon exhibited by the trees, Members of the Norwegian Association of peace across the nations and generations,’ in which the trunk shows a marked of Landscape Architects (NLA), including says Suzuki. ‘We are working on a Japanese, directional bend is known as the centripetal a former student of Suzuki’s, toured the English, and Chinese version of the A-Bomb phenomenon. Suzuki’s hypothesis is that A-bombed trees in Hiroshima. This inspired Tree Guidebook that summarises the results the damage caused by the blasts causes them to request seedings from these trees to of this research, and will release it in 2021.’ the growth rate on that side of the tree to plant in Norway as a gesture of peace. Suzuki The team hopes to promote recognition become significantly reduced compared to was asked to provide seedlings in time for of and information exchange about these the growth on the sheltered side of the tree, the ICAN Nobel Peace prize ceremony. amazing trees. There is much we can learn thus causing a tilt. The collaborators plan to ‘With the cooperation of the ANT-Hiroshima from these trees as living testaments to the take further measurements of the trees to and The Hiroshima Botanical Garden, power and the damage corroborate this hypothesis. ‘In the future, the seedlings were sent, and the Mayor of of war. l we will also perform simultaneous internal Hiroshima and Nagasaki donated them to and external measurement of A-bombed University of Oslo where they are growing trees using acoustic diagnosis of the internal very well,’ enthuses Suzuki. portion of the trees by Kanno and Negishi,’ Project Insights explains Suzuki. LEARNING FROM TREES FUNDING Currently, there is little legal protection • Grant-in-Aid for Scientific Research (C) The measurements recorded thus far have available for these A-bombed trees. Existing 2018-2021, 17K00680 been compiled by the team, together with Cultural Property Protection law requires • The Obayashi Foundation Support details on whether the trees have been assets to be healthy and beautiful to be Program for Students 2012 Nagisa Owaki moved and whether they have a single or recognised as cultural assets. However, the • Grant-in-Aid for Scientific Research (C) multiple trunks. While Suzuki noted that bombed trees are scarred and damaged. 2019-2022, 19K06115 many of the trees inclined towards Ground In addition, the management of the trees • Grant-in-Aid for challenging Exploratory Research, 2015-2017, 19K06115 Zero, there were a significant number that varies considerably, and no standard level leaned in seemingly random directions. of care exists for them. ‘While many have CONTACT However, once the team factored in that been registered by city authorities in their Professor Masakazu Suzuki

E: [email protected] E: masayan.r9.dion.ne.jp The A-bombed trees can be the messengers of peace across W: https://glh.unitar.org/ the nations and generations W: https://www.ant-hiroshima.org BIO Masakazu Suzuki graduated from Faculty many of the bombed trees had been moved respective cities, their management is left of Agriculture, The University of Tokyo. from their original locations, this further to the owner of the land on which each He is now Professor Emeritus at the supported their hypothesis by directional tree grows, and there is no uniformity in University of Tsukuba Department of Art statistics. the methodology of their maintenance, and Design. management or public use,’ says Suzuki. SEEKING RECOGNITION While in Hiroshima, there is a more ‘My dream is for the A-bombed trees to be generalised natural approach, where the recognised as part of the World Heritage growing conditions of the trees is nurtured, Site, in the same way as the Atomic Bomb in Nagasaki, there is more of a trend Dome,’ says Suzuki. The A-bomb dome towards artificial surgical procedures such was preserved and protected soon after the as stuffing the trees with resin or cement for bombings took place, but the affected trees reinforcement. ‘Despite this, the strength of have not received protection despite their the trees’ vitality and aesthetic beauty is really cultural and historical importance. Much can moving and impressive,’ says Suzuki. be learned from studying these damaged trees. ‘We can still see the distribution of The collaborators plan to conduct detailed damage brought by the atomic bombing measurements, observations and surveys in the cities even today. The distance and of A-bombed trees, identifying further trees direction from the ground zero can now be using domestic testimony and US archives. estimated based on the traces of damage They also seek to collaborate with authorities on the A-bombed trees,’ he continues. There to ensure the trees are protected and given have been many positive responses to recognition as historical and cultural assets. the work completed so far on this project. ‘The A-bombed trees can be the messengers

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