[2021.3.4 UPDATE]

聞き手：藤井一至、藤原辰史、青井哲人、松田法子

『土の文明史』（2010）『土と内臓』（2016）、『土・牛・微生物』（2018、いずれも片岡夏実訳、築地書館）の著者であるデイビッド・モンゴメリー氏と『土と内臓』の共著者でもある妻、アン・ビクレー氏に藤井一至、藤原辰史、青井哲人、松田法子がインタビューを行った。

土と人の距離

藤井一至──こんにちは。今回はありがとうございます。

アン・ビクレー──デイビッドもすぐ来ると思うわ。興味を持ってくれてありがとう。

藤井──「生環境構築史」では、私たちがどのように資源を利用し、次にどのような世界を目指すべきかを考えており、土、庭、そして私たちの腸を理解することはとても重要だと考えています。

アン──土、建築物、人間、植物。私たちは自然と分離できない。私たちはしばしば、そのことを忘れてしまう。

藤井──アンは植物学者であり、公衆衛生が専門と知りました。

アン──そう、私は生物学、とくに自然史が専門。植物に鳥にトカゲ。自然界で目にする全てだけでなく、隠れているもう半分（The hidden half of nature）はとても小さい。私たちはパンデミックにあって、微生物についてはよく知っている。ウイルスは生きているかどうかは意見が分かれるけれど。私の卒業研究は環境計画だった。構築環境における行動しやすさを改善し、食事を改善すること。これはもっと注意を払うべき生環境でしょう。

藤井──コロナ禍では公衆衛生への意識が高まります。都市の暮らしでは、「土は汚い」という人もいます。人と人ではなく、土と人の距離はいかにあるべきでしょうか。

アン──土が汚い、良くない、という場合には、土のある面だけを見ていることが多いのでしょう。都市の土に毒や汚染物質が含まれていたとして、それを汚しているのは私たち人間です。私たちは生きているもの、子ども、ネコ、イヌに対しては畏敬の念や共感を持ちます。そしてほかの生物が私たち自身の幸福と関わっている時には大事にします。地球や土の健康が私たちの健康と関わっているということを十分に分かっていないのです（パソコンが固まる）。

デイビッド・モントゴメリー──やあ！（別のパソコンから）　アンは凍結してしまったな。

藤井──はい、今日は著書の背景について伺っています。例えば、デイビッドはシエラ・ネバダで地質学に興味を持ったそうですね。

デイビッド──私はカリフォルニア、サンフランシスコの近くで生まれ、シエラ・ネバダやヨセミテ国立公園にハイキングに行ったものだ。それが地質学者になるきっかけだった。アンはコロラドで生まれ、大学でカリフォルニアに引っ越し、そこでガーデニングを始めた。

藤井──デイビッドもガーデニングを？

デイビッド──私もやるが、ボスはアンだ。彼女は生物学者なので、私は彼女の助手にすぎない。

藤井──土は岩石ゾーンと生物ゾーンの交差する領域だとされます。昨日ふと、デイビッドとアンも似ているなと思いつきました。

デイビッド──その通りだ。地質学者として、土ができるには岩石が崩壊して砂、シルトなど細粒物質が生まれるまで数世紀かかると思っていたが、生物が加わるととても早く肥沃になる。アンは庭でそのことを教えてくれたんだ。それは衝撃だよ。そこで私たちは土を回復させるには生物を再活性化させることが大事だと気付くことができた。私たちは土から希望を教えてもらった。

アン──庭でコンポストとマルチ（有機物による被覆）を始めてから数年で土の色が変わり、どんどん暗色になった。私たちの土は飢えていて、長い間十分に食べていなかった、有機物を。私たちは土から希望をもらった。もしも良い土がもともとあって、有機物をあまり入れていなかったら、こうはなっていなかったでしょう。

デイビッド──つまり、ひどい土のおかげってこと？

アン──そうではないけれど、大きな教訓を得たわ。

藤井──私は若干悲観的です、多くの環境科学者の例にもれず。デイビッドに近いでしょう。私たちに土は選べない、土はそう簡単に変えられない、しかしアンは希望を見出している。

アン──そう。『土・牛・微生物』では、農家が土を変えることを示してきた。数千エーカーを有する農家が土の扱い方を変え、それによって土はよみがえった。そのことから希望をもらったわ。千年にわたって土を傷つけてきたのは悲しい話だけれど、アメリカでも日本でもヨーロッパでも土に有機物を還すことで改善できると考えているの。

藤井──地質学的にはグレートプレーンズ（北米中央平原）、プレーリー（北米大平原）に氷河期に堆積した微細粒子が風食によって「ダスト・ボウル」（米国中西部で1931-37年に発生した砂嵐）という被害を引き起こした。機械化や集約化が土を劣化させたといわれます。このことは著作のきっかけになっていますか？

デイビッド──そう、『土の文明史』では過耕作が土から命を奪うことを学んだ。集約的な耕作と窒素施用の組み合わせが土壌有機物にとってはいかに快適かということを知って驚いたんだ。そこで、化学肥料の施用や攪乱なしに集約的な農業が可能となることを『土・牛・微生物』で書いたんだ。土について考え方を変えないといけないし、機械や化学肥料に依存した集約農業のスタイルについてもそうだ。このままで世界を養うことはできない。土を害するか、食料を生産するかというのは二択ではなく、非破壊的な食糧生産方法を探るための異なる選択肢があるんだ。

生物と人間社会の多様性

藤井──では、話題を変えましょう。私のちょっとした興味なのですが、生物学者と地質学者を結びつけたものは何でしょうか。失礼をお許し下さい。趣味かなにか共通するものはありますか？

アン──面白いわね。デイビッドは茶色い指（Brown thumb）といって、菜園でなんでも枯らしてしまう人なの。水やりを忘れて枯らしてしまう。緑の指（菜園に才がある）なら大丈夫。

デイビッド──それはアンのことなんだ。

アン──岩石のような無生物と生物がつながって生きた土になる。微生物やその捕食者が壊れると私たちの環境がなくなる。土は、すべての始まり。デイビッドと私は、物質循環のような自然のプロセスの重要性について同じ大きな枠組みを捉えている。

デイビッド──私たちは自然科学を専門としていて、自然への愛や感謝を共有している。分野は違っていても、お互いに自然を観察し、考える。何かに気づくと、「デイビッド、これ見て！」と言うことができる。

アン──同じように考える必要はないけれど、同じことについて考えることはできる。もしも違う考えなら、自分の考えを深めることができる。2つを一緒に考えると3つめの考え方になる。大方、3つめのほうがどちらか1つよりも良くなっているわ。

藤井──藤原さんから事前に来ていた質問がこの話題と近いですね。地下の生態系では何十億もの微生物が共存し、その多様性が維持されています。ここから、地上で暮らす私たちの生活になにかヒントは得られますか？

デイビッド──『土と内臓』では、農業と医療に共通して、土や私たちのなかに微生物がいることを示しました。これは微生物のことを考える以上に、異なる考え方をするという点で有益です。微生物は病原菌だ悪者だと、とくにコロナ禍では考えがちですが、農業でも医療でも私たちの毎日の食事でも、微生物が有益なこともしていることを知ることは有益です。私たちの行動次第で良くも悪くもなるのです。

アン──微生物の世界は理解が難しい。有用な微生物がいて、ウイルスにも有用なものがいるけれど、その考え方はなかなか受け入れられない。実際のところ、何をしているのかよくわからないけれど、悪者もいれば良い者もいる。多様性が重要という点では、土と腸内は似ている。カギは多様な食事で、それは土にも腸にも当てはまる。

藤原辰史──環境史を専門とする藤原です。緑の革命（戦後の途上国における肥料や品種改良による食糧増産）と機械化はコミュニティや地域社会を破壊したといわれます。ご著書では、生物多様性だけでなく人間社会の多様性についても考えさせられました。この点について、いかがお考えでしょうか。

デイビッド──講義では土壌の多様性が大事だという時に、もしも地質学者ばっかりなら社会は機能不全になるだろうという話をよくします。みんな餓死するよ。美術も音楽もなく、石の話ばかり。私が地質学者、アンが生物学者、あなた（藤原）が環境史学者。皆が同じことをするよりも多くのことができるだろう。この例は土や腸内にもあてはめると、なぜ多様な人々、考え方、職業、仕事、教育レベルが必要なのかがわかるだろう。野球に例えると、みんなが一塁の選手だと勝てないのと同じだ。

アン──アメリカ中西部にはローカルなコミュニティがあります。それはグローバル化した世界ではここ数十年厳しい状態に置かれていますが、依然として機能があるのです、デイビッドが言うように。先住の人々の持つ環境や農業の知識（どこがよくて、何がそこでよく育つのか）を失うのは、大きな問題です。農業に限らず、精神や人間性などのために必要なのです。

庭は脳の地図？

藤井──多様性に関して、腸内フローラに話を移したいと思います。私の読んだ論文では、アマゾンの先住の人々からニューヨーカーへと腸内細菌の多様性が減少することを報告しています。もっと自然と触れ合うべきなのでしょうか。食事の多様性、微生物の多様性について、自然や土との関わりについて考えをお聞かせいただけますでしょうか。

アン──そう、その種の報告はあるわよね。先住の人々は微生物についてより多様な環境に身を置いている。ニューヨーカーは自然と接点があまりなく、腸内細菌が少なくなる。スポーツの喩えは好きではないけれど、20 人の選手から選んだチームと2,000人の選手から選んだチームが戦うなら、2,000人の方を選びたいわね。選手が多いほうがいいのは腸内細菌も同じでしょう。

腸内細菌は栄養を必要とし、人間も栄養を必要としている。どんな食事で腸内細菌が増えるのかが重要だわ。単純な糖類よりも複雑な炭水化物のほうが発酵に関わる微生物は多い。これが異なる植物性食品を食べることが大切な理由です。人はコムギとお米とダイズとトウモロコシばかり食べている。たったの４つ。腸内細菌には多様とは言えない。25種類から選んだら、どうかしら。

藤井──昔、農家は糞尿などなんでも農地に戻していました。これは土には良くても、寄生虫が問題となっていました。公衆衛生の観点からはいかがでしょうか。

デイビッド──これは牛糞堆肥にもあてはまるけれど、うまく堆肥化できれば病原菌や害虫は出ないだろう。ほかの生物に食べてもらってコンポスト化できれば、今度は私たちの健康にとっても良いことだ。

アン──デイビッドと私は新しい本を書いています。反芻動物は植物を選んで食べてタンニンやサポニンを摂取する。寄生虫を排する免疫系になる。アフリカのチンパンジーにも腸内に寄生虫がいるけれど、寄生虫が苦手なベロニアという植物を食べる。その植物の生えている場所を守らないといけないという話にもなる。

藤井──出版社からの話は多いでしょう。こちらでは藤原辰史さんも日本のベストセラー作家で、同じ状況にあります。さて、庭に話を変えましょう。現在お庭では何を栽培されていますか。

アン──夏はバジルよ。秋はハーブね。永年性のルッコラ、ケール、葉菜類、トマト。

藤井──生産性の低い私の畑でもバジルだけはよく育ちます。消費するために、毎日パスタ、パスタ、パスタ。

アン──そうそう。

藤原──哲学を研究する友人は、庭とは脳の地図だと言います。あなたにとって庭とは何ですか？

デイビッド──私にとって、庭は美と安らぎのためのものだ。アンにとっては、行動とつながりと相互作用のための場所だ。アンは植物を移動し、計画し、デザインし、実験する。彼女は庭での出来事に関与し、私はそれを楽しんで見ている。広い芝生でボールを投げて犬を喜ばせるのもいいけれど、よく世話をした庭は多様性と美を生み出す。庭はアンの子どものようだ。

青井──庭を始めたのはいつですか？

デイビッド──家を買ったのは1997年。数年間計画を立てて、『土の文明史』が出版されたのは2007年。2006年には書き終えていた。そのあいだに変化が起こり始めていた。それで2人で『土と内臓』を書いたんだ。私が土の破壊について書いていた時、アンは逆のことをしていた。それで楽観的になったんだ。

藤井──生環境構築の目標は、限られた資源の消耗ではなく、自然資源の再設計にあります。

デイビッド──そう、健康と肥沃度を回復することは自然界と人間社会を持続的にし、自然の循環と一体化するために重要なことです。建築物を建てる時に基礎を疎かにはできない。そうでないと崩壊してしまう。自然界でも土に注意を払わないと、不安定になる。

藤原──“構築”という言葉は産業的すぎるように感じます。ご著書からは構築という言葉に違うニュアンスを感じる。固体ユニットの結合ではなく、ユニットのネットワークのようなもの。

青井──建築や都市計画の分野では、“構築”はコミュニティの構築という意味でも使います。人間の関係を再構築し、再構成することを意味しますので、違和感はないです。

デイビッド──土の再構築っていうのはいいアイデアだよね。自然のパターンを再統合し、再構築し、どうやってたどり着くのか枠組みをつくり直すかがカギになる。著書のひとつの目的は人々に、土や土との関係について考え直すように促すことだったんだ。作家としての仕事は、事実や科学や現実に基づいて人々の考えを形成し、影響を与えることであり、人々にこれまでの考え方を再評価し、異なる行動をするように奨励することだ。

藤井──植物学者がいないと地質学者は土を再構築できないとすると、アンがたくさん必要になりますよね。

デイビッド──クローンの出番だ！

アン──面白いわ。自然と関係なく生きているものなんていなくて、自然とのかかわりが生活を豊かにしてくれている。このつながりを忘れることが気候変動などの問題の根源だと思う。もっと本来的な園芸家が必要だけれど、それは庭を機械で草刈りすることではないの。

藤原──ありがとうございます。そろそろ講義なので行かないと。自然科学だけでなく歴史、社会科学、人類学も土と接続しています。そのことを考えるための希望を持てました。ありがとうございます。

藤井──私たちは希望があるから生きていけますね。

デイビッド──希望はいいよね。

生態学者と経済学者は共に働ける

藤井──アンが足りない、という話に戻りますが、ブラジルの有機農家を訪ねたことがあります。数千haの慣行農法をやる父親に反抗する息子が耕せるのは１haが限界だということでした。大規模にはできませんが、彼はどうやったらよいかほかのガイドや子どもに教えることができます。これは土の学校で、アンを生み出す方法かと思います。

アン──ハッハ。日本ではどうかわからないけれど、アメリカでは20代の多くの若者が大学を出たら農家になりたいと言っているわ。アメリカの農家の平均年齢は68歳だから、これは良いことだわ。若者は新しいアイデアも生み出すでしょう。土を活かすことは作物の健康にとってもカギだと知っているから、知識を再生産できる。殺虫剤と除草剤を減らし、気候変動や作物の栄養不足といった問題に対処する。そこには希望が持てるわ。

藤井──もうひとつ質問です。動物園のフンやスターバックスのコーヒーかすは今も使われていますか？

アン──そう、どっちもあるわよ。パンデミックで今はどうなっているかわからないけれど。でも、草食動物は常にフンをしているし、コーヒーも飲み続けている限り、コーヒーかすは出るでしょう。どれもいい有機物だわ。特に庭の樹木はどんどん大きくなって毎年有機物を生み出すので、だんだん外の資源に頼らなくなってきた。

デイビッド──有機物を運び入れる人から、持ち出す人になった！

藤井──『土と内臓』を読んだあとに、スターバックスにコーヒーかすをもらいに行きましたが、断られました。「ゴミですので、差し上げられません」と。

もしかしたら、地質の違いが有機質資材の需要に影響しているかもしれない。シアトルの氷河堆積物ではなく、日本は火山灰で土は黒い。有機物に困っていない。シアトルでは堆肥は需要ありますか？

アン──シアトルでは、コーヒーかすは人気よ。スターバックスは無料で配ってる。あと動物園の堆肥と木材チップも。私は木材チップが好き。農場の一部を有機物置き場にして堆肥化するのは合理的ね。

藤井──都市は廃棄物を田舎から集積します。例えば、インドやアフリカでは堆肥はあっても建築材や燃料として使われ、土に播けません。資源は均一に分配されていません。

デイビッド──それは農業や環境問題であると同時に社会問題でもあります。建築材や燃料の代替手段を生み出さないと問題は解決できない。

藤井──そうですね。例えば、アマゾンの熱帯雨林を伐採したり燃やしたりというのはエコロジーではなく、エコノミーの原則に従っています。お二人には地下の生態系から学んだ原則があると思いますが、生態系と経済の両方の原則は重要で、かつ両立すべきものですよね。

デイビッド──そう、相乗効果があるはずだ。

アン──そうそう。生態学者と経済学者は共に働ける。経済学者は市場と需要と供給を、生態学者は自然のプロセスと土や水のような資源についてよく知っている。

デイビッド──生態学の重要な視点は、ループで閉じる循環の価値にある。一方、従来の経済理論はインプットがアウトプットを出す直線の一本鎖だ。自然のエコノミーの効率的なところは、リサイクルにある。

青井──これまで旅行した場所で感銘を受けた場所はどちらでしょうか。

デイビッド──感銘を受けたのは、『土・牛・微生物』のインタビューで訪ねたガーナのコフィ・ボア氏です。彼は自給自足の農業に保全農業を適用し、成功しました。

アン──私はコネチカットとカリフォルニアの農場を訪ねた時だわ。土のことをよく世話をしていた。狭い土地で多くの作物を栽培していたわ。コネチカットでは30～40種類。そして、その地域の環境や土についてよく知っている。

松田法子──あなたが自分の庭づくりに参照した理論などはありますか？

アン──特にないわ。植物をもってきて、育て、最善を尽くしても死んだり、病気にかかったりすると、この庭にはいたくないんだと考えます。土と植物がいい関係ではない、庭にいたいと思う植物に切り替えよう、と。これは試練だわ。農家だったらこんなに時間はかけないし、繰り返し失敗はしないでしょう。家庭菜園で失敗するのは植物の言っていることを無視する場合です。デイビッドの言うように、植物と土をよく観察することが私の理論です。植物とのコミュニケーションは難しいけれど、植物や土の表現方法を知れば、生産的な方法で対応できる。観察し、学ぶようにしている。本を読むように、庭を読むの。最も良い菜園には園芸家が必要ない。植物は賢く、土も良いので、庭は自分自身を世話できる。強くて美しい庭であることの証は、誰かが見て「すごい！　時間とお金と労働力をかけたでしょう」と言い、それに対して「いいえ、すべては植物のやったこと。場所を提供しただけよ」といえる状態にあることね。

松田──そうですね。ところで冬は市場で野菜を買わないといけないでしょうか。

アン──幸運にもシアトルには一年中やっている素敵な農家の市場があるの。私たちには腸内細菌のためにやっている食事法があって、半分が野菜なの。あとはその他、鶏肉、たまにデザート。多様な食事が健康に欠かせない。

デイビッド──これは証明しにくいけれど、血圧やコレステロール値にいい影響があるんだ。

アン──季節を通して違う野菜が手に入る。今は芽キャベツ。蒸して、ほんの少しの塩コショウとオリーブ油で食べる。今晩の一品ね。一年を通じて違うものを食べるのが腸内細菌にはいいわ。

青井──あなたは良い園芸家でもあり、良い料理人でもあるのですね。

藤井──今日はありがとうございました。


［シアトル：2020年11月16日16時〜／東京・京都：11月17日9時〜、Zoomにて］

Fujii: Thank you very much for joining interview for David and Anne.

Anne: Thank you for your interest. David should be joining us separately. He will come later. He should be here just in a minute or two.

Fujii: Okay. So, we would like to learn the hidden half of David from you. I'm a soil scientist, but most of the other members major in architecture, not pure architecture, but the boundary between the environmental history and architecture. So the topic is habitat building history for humans. How do humans change or utilize environmental resources, how do humans modify or exchanges resources, how do humans destroy them, and where should we go in the next stage? For us, the soil, garden, and the gut are very important factors and that's why we request you to join in our interview of our web magazine.

Anne: Yeah, that sounds good. What you're talking about is the relationship between the soil, buildings, people, and plants, that's all very important. As you know from our book, The Hidden Half of Nature, we're not really apart from nature. We're not separated. We have forgotten that in some ways.

Fujii: I learned from your book that you are a botanist and you worked in public health, as well.

Anne: Yes, my background is in biology, primarily in natural history. So, that’s plants, birds, lizards, you know, all of the parts of nature that we can see. Much of the rest of nature you can’t see, so that’s why we call it the hidden half of nature. It's too small. But of course we know about microorganisms, especially now in a pandemic. Although some say viruses are not alive, they're nonetheless grouped with all of the other microorganisms. My graduate work was in environmental planning, how we design and build places with the environment in mind. I have also worked in the public health field, on policies and programs to try to make the places that people live - our cities, our streets, and all of that - better for us. The aim is to make getting physical activity easier in the built environment and also improving people’s access to healthy food. These things are part of human habitat that we really need to be paying much more attention to.

Fujii: So regarding public health, sometimes urban people tend to say “soil is dirty” and when the COVID issue occurs, we tend to request public hygiene too much, you know, so the distance between human and soil, not between person to person is difficult. What do you think about that?

Anne: I think that few of us have a deep enough understanding of soil because when you only see one side of it you think that’s everything. You see and think about the perspective that soil is dirty, soil is bad. We can't have it around us. And these days, especially in urban environments, when we say, oh the soil has toxins and pollutants in it. But whose fault is it that soil got polluted? That's us, dumping and pouring things into the soil. So I think if people were to see soil as something that is alive, they might treat it better. We are alive, and most of us have a reverence for life so when we see other life, you know a seedling, a child, a cat, a dog, whatever it is, then we can have empathy and then we want to know more. And then most of the time, if you see that other life is related to your well-being you want to take care of it. And of course, this is the whole problem of our planet these days. Not enough of us realize how the health of the planet is connected to our own health. And so if we could get more people to see soil… (PC freezed)

David: Woops! Has she frozen? Hello!

Fujii: Yes, frozen. Today, we can learn a lot from your book, but we would like to have an additional information regarding background, for example, you started your interest of geology from Sierra Nevada.

David: Well I grew up in California, close to San Francisco. And when I was young we would go hiking in the beautiful Sierra Nevada and Yosemite National Park. It was an invitation to become a geologist. Anne grew up in Colorado. We met in California after she moved to California for college. She started gardening in California.

Fujii: So, are you also interested in garden or not?

David: Yes, mostly in using the garden. Anne is a mastermind of the garden. She is the gardener. I'm the gardener’s helper, because she's a biologist.

Aoi: She talked about that before getting frozen.

Fujii: Soil is a boundary area between biosphere and lithosphere. I thought yesterday oh! Anne and David may correspond to biosphere and lithosphere.

David: That's actually pretty true. My interest in soils started with just breaking down rocks to make soil and it took me a long time to become fully aware of how important the biology is and a lot of that was from watching and fix the soil in our garden because it happened so fast relative to what a geologist usually thinks in terms of making soil. There's two ways to think about how to make fertile soil. The way a geologist thinks about it is you start with a rock and you break the rock up and then it becomes more fertile as the biology gets integrated to it, but it takes a very long time to weather and break up rocks. So I was thinking oh, you know, it takes centuries to make an inch of it. And for making soil from scratch, that's pretty true. But if you already have the geology and it's broken up into sand or silt or loose material adding the biology can happen very fast—and that's what Anne taught me in our yard. You know, I knew this. But you really get it when you see it happen in your yard, when you see it happen at home in front of your face. It has a big impact on you. And a that's why we together realized that to restore soil if you already had some soil on the landscape a lot of it boils down to re-energizing the biology to bring the soil back to life.

I think we learned hope for the soil within, what was it, maybe two three years after Anne started composting and mulching. We started to see the soil start to change color. It was getting darker and it kept getting darker. Oh, we noticed after a couple of years and we were like, this is getting better. And then the worms came in and the soil just kept getting better and better. The longer she went on with her composting and mulching and changing the soil to make the garden, the more optimistic we became because it became very clear that you can take degraded soil and you can improve it very quickly.

Fuji: And how long did it take you to become more optimistic?

Anne: A short time, I think maybe just about a year or so after adding organic matter we started to see some kind of change. Our soil was so hungry and it had not eaten much in such a long time that it was very ready for all of the food, for all of the organic matter. It went from nearly dead to rapidly alive. That is what gave me hope you know, we started with such a bad condition and then it changed so quickly.

David: Are you saying it's a blessing we started with terrible soil?

Anne: No, it was a big lesson we learned.

Fujii: I'm a bit pessimistic, as most environmental scientists are. I'm close to David. We tend to say you can't choose soil, you can't change soil easily, but you have more hope than I.

Anne: I think so because I saw what happened in the garden. And then the third book Growing a Revolution showed how farmers can change soil. Some farmers in the U.S. have thousands of acres and they started to change how they treat the soil and then their soil began to improve and come back to life. And so that is what gives me hope. You know, I think if every gardener in the U.S., Japan, and Europe, everywhere really, started returning organic matter to the soil we could start to turn the whole ship around. Harming soil, that has been the whole sad story for millennia. But we can turn this around and that gives me hope, as there are not a lot of parts of the environment that we can restore as quickly as soil.

Fujii: Based on geology, the very fine particles deposited in the Great Plains or Prairie in Glacial age and then wind erosion caused “dust bowl”. The heavy machinery or intensive agriculture is known to damage soil. Is there any relationship between such past events and your desire to improve too intensive agriculture?

David: Yeah, I think that one of big lessons for me in writing the DIRT book was just how damaging disturbing the soil is. So all that big machinery ripping through and turning things over all the plowing, the tillage it's incredibly destructive for soil life. I was impressed to learn just how destructive it is to soil organic matter, especially when you combine intensive tillage with intensive nitrogen fertilization. It basically promoted the breakdown of organic matter and the loss of the soil. So it's a double bad and I think though that one of the things I learned in writing Growing a Revolution was that you can do intensive agriculture without the disturbance and without as much in terms of the chemical fertilization. But you have to think differently about the soil and so also the style of intensive mechanical agrichemical agriculture we've practiced in the 20th century going into the 21st century. It has been very destructive to the soil, but I don't think we have to rely on that to feed the world. It's not a choice between the two, we have a different option for how to explore less destructive practices, but that may be equally intensive in terms of growing food so they can be very productive but less damaging.

Fujii: Thanks, I would like to change the topic. It's just my curiosity, but what connects the biologist, Anne, and geologist, David? It's my curiosity, sorry. Do you share hobby or something?

Anne: That's funny. David will tell you that he has a brown thumb. What that means is a person who can’t grow plants because they forget to water them and that sort of thing, so then the plants die. But if you have a green thumb, it’s very easy to grow plants. (David: That is Anne) So, that’s why between the two of us, I am the gardener.

Fujii: I am also a brown thumb.

Anne: The connection comes because the parts – dead things, like rocks, plus living things like the plants and so forth – are what makes the whole environment of a living soil. We need to have the microorganisms. We need to have the predators and the things they eat because that is what sustains life. And when this network, the web of relationships starts to fall apart, then we get problems. Soil is at the beginning of everything. Most everything started out at one point eating plants and it wasn't until much later in the history of life that animals begin to eat animals. But if we ever lose the soil then we lose the plants and then we will have lost ourselves. And so I think for David and I, we see this bigger picture of the importance of everything—natural processes like nutrient cycling, how they all relate to one another to give us an environment that is much bigger than any single one of its parts. That's what soil is.

David: We are both trained in the Natural Sciences and we share a love and appreciation for the natural world. And so I think that's instead of having the same hobby. Of your overlap there. It's our basic outlook on the world a fairly similar, but from different disciplines, but we're also both I think trained to observe and think about the natural world. Those things come together in the garden. It was kind of a natural outgrowth where she would notice something and she'd go, “Dave. Look at this,” or where I would see something and it's that cross pollination with a common worldview and similar sort of ways of approaching it in terms of observing and thinking and asking questions.

Anne: You don’t have to think the same as another person, but you have to think about the same things. And so that's a big difference because if you think about the same things, the other person often has a different perspective on it and in that way it deepens your own perspective. And so there is Dave's way of thinking and Anne's way of thinking. When you put them together there is a third way of thinking. Hopefully most of the time this third way is better than either one of us.

Fujii: Fujiwara san’s question is related to this topic. You learn a lot from the hidden half of nature and that there is a very huge community of microbes and there are billions of microbes coexist and the high diversity is maintained in somehow. It is very interesting for me. And can you get some insights for the apparent half of nature?

David: In writing The Hidden Half of Nature a lot boiled down to thinking about how in our own lives and in both Agriculture and Medicine having the perspective that there are the microbes within us and on us or in the soil around the roots of a plant are there can benefit the host organism. It can actually be helpful to us in this kind of a different way of thinking than most of us are accustomed to thinking about microbes. We think about them as germs, as bad things and for good reason — I mean the current global pandemic is an excellent example of why that is the case. But there's this other half to them that we haven't fully appreciated and many of our practices in agriculture and medicine and even just our own dietary practices—what we choose to eat—don't always line up with how those organisms could help us, could be a benefit to us if we paid more attention to them and cultivate beneficial ones while trying to exclude the pests and pathogens too. I think there's a big lesson in learning to see the hidden half of nature, the microbial world, as not just a bad thing. But then it's something like with so much of nature. It can be good or bad depending on how we interact with it and that it's our actions that are setting up a lot of what they then can do either for us or do to us. We need to be more mindful of what we're eating so that we're feeding the beneficial ones inside our gut, and of what we're doing in the soil so that we're cultivating the life that will benefit our crops rather than attack our crops. It sort of reframes the way we look at that part of nature and I think it can help us in terms of soil fertility or own individual health in terms of all those maladies and chronic diseases related to disruption of our microbiome, which can be traced back to how we're thinking about provisioning them. Not disturbing them, feeding them what they need, and then cultivating a diverse community of life are the same three things that work in the soil and work in our gut what Anne and I call our inner soil. Anne do you want to add anything to that?

Anne: I think that captures the duality, you know that the microbial world is hard for a lot of people to understand. And it's really hard these days I think to talk about beneficial microorganisms because all we're thinking about is disease and so to start saying, you know, there's actually some beneficial viruses out there and we don't know much about them, that’s hard for people to accept. In fact, we don't even know all the viruses that are out there and we don't really know what they're doing. But just as there are the bad actors there are the good actors. You'd mentioned at one point all the biodiversity in the soil. I think about soil like the gut in many ways. So the key is a diverse diet for microbiomes, the one in the gut and the one in the soil, whether it's organic matter on my dinner plate or in my wheelbarrow. I want lots of different types of organic matter because somewhere out there in the garden and somewhere in me, in my gut, there is a microorganism that's going to thrive on that particular kind of organic matter. This is a relationship. This is part of the hidden half of nature and what keeps it working like it is supposed to work. We can keep it functioning normally or abnormally, and of course normal function is best. If we can just get the microbiomes of our gardens, our farms, and our bodies to be functioning as normally as possible, most of us I think would be noticing a difference in how our plants grow, if we feel well or sick, and those sorts of things.

Fujiwara: Ok, I'll be nice to see you. I'm Tatsushi Fujiwara from Kyoto to University. I am an environmental historian really interested in some for example, history of tractors and some history of rice breeding some. Yeah, that's why I love your books, a testament for me. Yeah, I'd like to ask you about the diversity. For example, the Green Revolution and the big machinery sometimes destroy the human communities and sometimes destroy the relationship between people and local society, but I think your books have a lot of things to think about the diversity of human society as well, not only the biological diversity but also the diversity of people or human nature. What do you think about this?

David: Yes, I would agree very much and one of the examples I like to use in lectures to convey why diversity in the soil is important usies the example of a human village or a town or a city where if everybody was a geologist. It would be totally dysfunctional. We would all starve and there would be no art to be no music. We’d just talk about rocks. And so if you look at what people have been able to do by engaging diverse communities where I can be a geologist, Anne can be a biologist, and you can be an environmental historian. You put that all together. We can do more things and we can learn more and engage with the world more than if we all did the same thing. And so I think we can take that same example into the soil or the human gut to understand why diversity is important and you know, you can always turn that around the other way to of why as a good example of why we want to diversity of people, a diversity of perspectives, and a diversity of professions, a diversity of jobs and education levels. There's a lot of strength in diversity by being able to do more things and to have specialty players. Look at a baseball team. If everyone was a first baseman, you wouldn't win, you need lots of different positions.

Anne: We seem to have lost an appreciation for the many local farming communities spread throughout the U.S., especially in the Midwest. It's been really hard for at least the last several decades for a lot of the smaller, family farms to thrive and remain functional in the way that David was just talking about. And to me that's a big problem because it means we're losing the knowledge that farmers have about these places from an environmental and agricultural perspective—knowing how the land works and what crops grow best in the place. Every single one of these places in the U.S. at one time or another grew a particular kind of wheat, a particular kind of wine grape, yes, wine grapes even in Kansas! There were certain breeds of animals that did best in these regions too. And so you had this whole array of food. We lose a lot by going to a globalized world and it makes it tough for all these smaller communities. The loss of culture, like what has happened to indigenous people around the world, including here in the U.S. translates into loss of knowledge and understanding about landscapes. At some point we don't really know what we're losing until it's gone. All of this kind of knowledge and experience is part of the strength of every country. Localized knowledge and experience represent the diversity of places and we ought to be trying to support that sort of thing, not only for agricultural reasons, but just for humanity, and for our spirit and those kinds of things.

Fujii: Thank you. Regarding diversity, I want to move on to the topic of microbiome diversity. I read one paper regarding the microbiome. The microbiome diversity decreases from wild apes, Amazonian people, and then New Yorkers. What do you think about the food biodiversity and the microbial diversity in terms of the interaction with nature or soil, the hidden half of nature? Maybe we need more interaction with nature?

Anne: Yes, I have seen papers like that and I think what it tells us is that we're really a part of nature. And so when you study Amazonian people and you see that the diversity of their microbiome is greater than what you find in the average New Yorker, this tells us that probably the indigenous Amazonians are living in pretty diverse environments, microbially speaking. And this is most likely why their microbiome is more diverse. And because the environment around us is the source for our microbiome, we want to be able to draw on that diversity as the microbiome develops, which is especially important in the first few years of life. Having more diversity to select from is usually a good idea in biology. But, if you live in an urban environment like New York City and you just don't have much contact with the natural world it can limit the composition of the microbiome. I don't normally like sports analogies, but now David put one out there. So I'll just say this—if you're trying to put together your baseball team and all you have is 20 people to choose from versus having 2,000 people to choose from, I’d rather select from a group of 2,000 people. That's how I think about our microbiome. You want to have lots of potential players to choose from.

Anne: The microbiome needs nourishment and the human being needs nourishment. And so making sure we understand what kind of a diet the human microbiome thrives on is really important. There are members of the human microbiome that ferment complex carbohydrates, and so if you give them a simple sugar molecule that’s not enough nourishment. This is why eating a lot of different whole plant foods is so important. We are stuck on wheat and rice and soy and corn for the most part. That's only four things. So this is not a very diverse diet for our microbiome. I mean, can you imagine if we had like 25 cereal grains to choose from?

Fujii: In the old days, farmers have provided everything, for example poop and urine and everything into the farm. So that was a good management in terms of soil. But, at the same time, the human health is annoyed with parasite issue. So such a public hygiene issue and such a diversity issue is not so simple problem.

David: There's issues with returning raw cattle manure to the fields, but there seems to be pretty good evidence that really good thorough composting, whether of human waste or of cattle waste, can do a really good job at eliminating most pests and pathogens. If we compost them and if we basically manage them by having them get eaten and replaced by other organisms, we can sort of turn it so that is promoting health for us.

Anne: The way I think about that issue goes back to my idea about a functioning soil. If you have a high functioning soil microbiome, the parasites and even the microbiomes of those parasites get dropped into the soil and encounter many other microbes and other kinds of soil life. There is less likelihood of the parasite being able to continue their life cycle undisturbed because something is likely going to eat them or they’ll find the habitat inhospitable. David and I are now we're working on a new book and there is research on how ruminants (cows, goats, and sheep) select different combinations of plant species for their phytochemicals, like tannins or saponins. These phytochemicals make the gut of a ruminant inhospitable to the parasite and it will also boost the immune system of the animal in ways that expel parasites out of the body. So this is a way that we can use plant diversity in the diet of livestock to help control parasites. Animals in the wild routinely do this. Studies done in Africa on chimpanzees, actually out of a university in Japan, found that they used specific plants to control certain parasites. Animals in the wild have always had parasites, maybe they are a part of the macro biome. Anyway, a plant called Vernonia works to scour certain parasites from the guts of chimpanzees at the time of year that the parasites tend to be really bad. But of course for chimpanzees to have access to Vernonia it is necessary to protect the places the plant grows.

Fujii: I guess that you have many requests from publishers. Here, Tatsushi Fujiwara is a best seller writer in Japan and he should also be in same situation. Anyway, another question is related to your garden. What crops do you grow now in this summer?

Anne: Last summer we had a lot of basil. Now it’s late fall and at the moment we have some of the hardier herbs growing. But we also usually have a perennial arugula, kale, and other salad greens. I also experimented with growing tomatoes last summer to find one that can do well in our short summers.

Fujii: This year, I was annoyed with very low productivity of garden, but basil is an exception. To consume this, I eat pasta, pasta, pasta.

Fujiwara: One of my friends studying philosophy said that gardening is a map of the brain. What is garden for you?

David: For me, the garden is mostly about beauty and refuge. It is a place to be, for Anne and I to enjoy and so for me as to a garden much of it is visual, just being around nature and trees, the whole concept of nature bathing—place to go have a nature bath. But I think that Anne has a bit of a different perspective because for her it's also about doing and action and relationships and interactions, she likes to move plants and plan and design and manipulate. So she's more directly involved in what's happening in the garden and I'm more involved enjoying it.

We have different sort of views of what is the garden in our lives that are framed by how we relate to it and how we use it. I'll admit that when we first bought the house and we just had a big lawn everywhere. I was okay with it. That was fine. You know the dog liked it, I'd throw a ball and the dog would go get it and come back and it was fun. But I've really come to appreciate how much the diversity and beauty of a well-tended garden can actually bring into your life. We now live between the garden and house in the summer. We move outside as much as we can because it's nice and it's in the garden and that and you get that relationship. I didn't expect that when Anne started a garden. So she is the boss of the garden. She's the one who really designed it laid it out did most of the work it's her. It's her baby.

Aoi: Simple question. What year did you start creating your garden?

David: We bought the house in 1997. And then, we took a couple of years to plan and think and do some remodeling on the house and then started most of the big work on the garden. I was finishing writing DIRT, the book that came out in 2007, so I finished it in 2006. So, the timing of when I was sort of actively writing it was when we were just starting to see big changes in the yard. Yeah, and it was and that's one of the reasons why we wrote The Hidden Half of Nature together. I had just written a book about the destruction of soil and here she was doing the opposite and was rebuilding soil in the yard and doing it really fast. This is what started the conversion to optimism on this issue.

Fujii: Our final goal of habitat building history web magazine is to propose how to move from the destruction of the limited natural resources to the rebuilding of the natural resources. That is very close to your topic.

David: Yeah, restoring health and fertility to the soil is the common foundation to restore the natural world and to make human societies more sustainable and integrated with natural cycles. You can't ignore the foundation. If you were to rebuild a building you pay attention to the foundation because otherwise your building will collapse and I think we're faced with the same thing in terms of the natural world where human activity is now such a dominant force in nature that we have to pay attention to what we've been doing to the foundation for it, which is the soil and reframe our thinking, and reframe our actions really do things differently because otherwise the remodeling that we're doing to the natural world will be on an unstable basis.

Fujiwara: The word “building” is too much industrial for me. But I think the nuance of the word “building soil” of your books is a little bit different. I can learn from your book that building in more modern times changes from combining solid units to networks connecting units.

Aoi: In our field of architecture and urban planning, we also use the word “building” as in “community building”, for instance. It means rebuilding or reorganizing the human relationship. So it’s natural for me.

David: The idea of rebuilding soil is a good idea. The idea of trying to take natural pattern and reintegrating that, rebuilding it, and reframing how we think to get there is really the key. And that's actually one of the big goals behind our books is to try and encourage people to think differently about the systems we’re writing about how to think about the soil and our relationship to it because if you think about how we act you know, how we perceive how we frame a question really sort of sets the terms on which we consider what kinds of actions to take. We're so excited to do both the soil and the human gut in terms of the hidden half of nature, having those two really different systems and drawing the parallels between them. I think that part of our job as writers is to try and shape how people think, and influence how people think and know in ways that are grounded in fact and science and reality. But that will encourage people to re-evaluate how they conceived of the way they act and therefore potentially follow through to act differently.

Fujii: Without botanist, the geologist can't rebuild the soil. We need Anne, right? It is a serious problem for me. To grow revolution, transfer perspectives, and extend techniques, quite a few “Anne” are needed.

David: Yeah, that's where cloning can come in!

Anne: You know, that's an interesting idea. I have a lot of concerns about modern life, one of them is that as we push ahead with our technology and as we push ahead with ignoring what nature is capable of, and what she has been doing for millennia, we start to forget things. No matter where you go, there were people before us in the early days of agriculture who had always known how to get plants in the ground and how to grow them. They had crop failures to be sure, but they were able to understand we can't wreck this place because then we're not going to have any food. And part of taking care of the place is knowing these things. My concern about modern life is that we're losing some very basic skills like knowing how to grow and take care of a plant. When we wall ourselves off from nature that’s not good. We forget that we once did nothing but interact with nature and that many of those interactions enriched our lives. Forgetting this history is part of the root of problems, like climate change. We are all being very affected by that. I like the idea of more real gardeners. By that I don’t mean a person who shows up with a truck filled with machinery and blowers that make a lot of noise and use energy. Some of them are perhaps not even helping the homeowner that much because I don't think there's very much learning going on between the plant and the person. So when we treat nature like that, we're really short circuiting the connection we have with nature. And that's partly why I like the idea of a green building where plants are an integral part of the building say on the south facing side. You can use vines and trees to provide cooling shade and to cover the parts of the building that are not nice to look at. So I think there's a lot of room for gardening and gardeners out there in the world.

Fujiwara: Thank you very much. I have to leave here because I have a lecture from now. So I would like to connect the soil from the Natural Science, but also history, social science, and the humanities. You have a lot of hopes to think about that. Thank you very much.

Fujii: We feed on hope, right?

David: Hope is good thing.

Fujii: I go back to the talk about of a limited number of Anne. I have visited the Brazilian organic farmer. He fights against his farther who organized three thousand hectare of intensive agriculture. On the other hand, he did one hectare of organic farm and said that he wanted to expand thousand-hectare organic farm, but one hectare is the maximum for him. But he can teach how to grow plants, how to manage farm to other guides and kids. This is school of soil and it would be one answer to regenerate Annes.

Anne: Haha! I don't know if this is happening in Japan. But here in the U.S. we have many young people in their 20’s coming out of college saying they want to be a farmer and have a farm. I find this very hopeful because the average age of an American farmer is something like 68 and that is a really big problem because soon those people are not going to be here. Young people coming into farming bring new ideas. Many of them are interested in regenerative techniques, because they understand that a living soil is the key to healthy crops. It's the key to getting off of the pesticides and the herbicides and it's a way of dealing with so many other problems that we have from climate change to decreasing nutrient and phytochemical levels in crops. So I'm really hopeful about that. And in a sense, I see these younger people as the true gardeners, they're now infiltrating agriculture and I find that inspiring.

Fujii: Another question is can you get the poop compost from zoo or coffee ground residues from Starbucks Coffee shops?

Anne: Yes, both are still happening, although in the pandemic I don’t how it is working. But the animals at the zoo are always pooping and so there is still composting the herbivore poop going on. And as long as everyone keeps drinking coffee, Starbucks will keep having coffee grounds. All of the plants in the garden, especially the trees, have gotten bigger and bigger and they are shedding more and more organic matter every year. The garden now provides so much organic matter that I don’t rely much on outside sources like I used to. I think it’s possible for every garden to generate enough organic matter for itself. I don't know what that means for the zoo-doo or the coffee grounds, but somebody will be able to use those still I think.

David: From being an importer of organic matter to being an exporter of organic matter.

Fujii: After reading your book, I request the Starbucks shop in Japan to give me give the coffee grounds, but they refused my request saying “Providing coffee ground residue is prohibited. It is just a garbage, garbage, no, no, no.” I think geology makes gap of coffee ground residue use between Japan and Seattle. We have black soil, so we don't need so much the only additional organic matter. Maybe in Seattle, glacial till requires more organic matter. So there is high demand for the coffee ground residues. Is it popular in Seattle?

Anne: Yes, coffee grounds are still popular here in Seattle. There is lots of demand and the same with zoo-doo. Starbucks is still packaging them up and giving them away for free. Also in demand in Seattle are wood chips. When a tree dies or gets pruned arborists chip the wood into small bits and give it away. I really like wood chips, they are very good in my mulch mixes. In fact, my neighbor and I are trying to get some right now. So there's still a lot of demand for organic matter in in Seattle. And this is where I think about a farm, especially a good size farm that has a lot of space. They have places to store all of this organic matter that's being generated on their farm from the animal manure, all the dead plants and dead plant parts. Dedicating a part of a farm to processing and storing that stuff makes really good sense.

Fujii: Urban areas usually accumulate waste from rural area. For example, in a remote rural area in Africa or India, peoples have manure, but they have to use the manure for building house or sometimes for fuel resources and they can’t spare manure to soils. Resources are not uniformly distributed.

David: When you think about sort of managing the world soils,it's as much a social problem as it is an agronomic or environmental problem still that you can create opportunities for people like that to have other ways to either build their houses or to cook using fuel. You have to solve those problems in the context that they existed otherwise solutions won't work.

Fujii: Yeah, for example, cutting or burning of the Amazonian forest follows the principle of economy, not ecology. You learn a lot of the principle from hidden half of nature, not the principle of economy. Both principle should be important and compatible, right?

David: Yeah, it's finding the synergy.

Anne: Yeah, the world would be a different place. If we had ecologists and economists working side-by-side. The economists know about supply and demand and markets and the ecologists know about the natural processes and the resources that support human life like soil and water and all the rest.

David: I mean the fundamental insight comes from ecology is the value of cycles of actually closing the loop, whereas most conventional economic theory is about chains. It's about a linear input and output back to the input, whereas nature is brutally efficient in her economy, and it's all about recycling.

Aoi: Maybe you travel many different places across the world. What is the most impressive place or people's way of life in your experience, David and Anne?

David: I think for me the most impressive visit I had was with the gentleman named Kofi Boa in Ghana who I interviewed in Growing a Revolution. He was someone who had adapted conservation agriculture to subsistence farming in rural Africa in equatorial West Africa, and was very successful. That deeply impressed me.

Anne: I think about a couple of vegetable farms that we visited for the new book and they have a very small amount of land, about a hectare and a half or so. One is in Connecticut and one is in California. I noticed similarities even though each farm has a very different climate and soils. Both farms had densely planted beds. And the minute one crop gets harvested something else goes into its place along with organic matter, and they also do other practices that take care of the soil. It was just constant motion and nutrient cycling. The other thing about both of the farms was that they grew many different kinds of crops on very little land. Bryan, the farmer in Connecticut, had about 30 to 40 different crops going at the peak of the season. The other very impressive thing is that both the farmers knew enough about their local environment and their particular soils and had figured out over the time what works and what doesn't work for their land and they never stop learning. The farmer in Connecticut wrote a book about all he has learned and the methods he developed to take care of the soil. These two farmers are also thinking about how they will deal with climate change, what crops they might change to, how they can keep farming. Again, the amount of food they grow is quite impressive, and how diligent they are about taking care of the soil and how smart they are. We might write books and think ideas and talk about these things, but these two farmers are seeing things happen in real-time and the next minute they apply what they’ve learned. It was very exciting to visit them.

Matsuda: Do you have theory to create your garden?

Anne: For example, if there's a plant that I've put in and then I really nurtured it and I've done my best, and that plant dies, or the plant is ailing, or it's getting attacked by pathogens, that tells me things. That plant doesn’t want to be in the garden and it doesn't have the right relationships with the other plants and the soil, so it’s time to let that plant go, to let it die off and replace it with a plant that wants to be in the garden. This is a very hard lesson. A farmer would never spend so much time with a single plant and a farmer would never plant the same failing crop again. Some gardeners ignore what the plant is saying, so my theory on all this goes back to David's point that you have to look and you have to observe both plants and soil. Even though there is a bit of a language barrier with us right now, think about communicating with plants, it’s really hard. But, if you can learn the cues and the way plants and soils express things, then you can respond in a productive way. So even after all of these years in the garden, I try as much as possible to always see and learn. If something makes me turn my head because it’s not quite right I think that plant is talking to me. I'm going to investigate and see if I can make that a happier plant. It is like you are reading your garden the way you can read the words in a book. They all add up to a story, or subplots, or just a simple point. I try and approach things in a garden this way. It's challenging in these times because even in Seattle with all of the rain we get, the summers have become hotter and drier and the plants are telling us this because some of them are dying. And so that's on my mind. I think the best garden could almost be one that doesn't need a gardener because your plants are so smart and the soil is so good that the garden can kind of take care of itself. The sign of a reslient and beautiful garden is if somebody comes into the garden and they say “Wow, look at this place. You must put all kinds of you know, time and money and work into it” and then you say, “Oh no, this is all of the plants. They know how to do this. We're just providing a place for them to be a plant.”

Matsuda: Yeah, but you should buy the vegetables in winter season from market.

Anne: Oh, we're fortunate here in Seattle that we have good farmers’ markets that run all year long. I like to have things on my plate for my microbiome—there is a picture of the plate in The Hidden Half of Nature—about half of my plate with vegetables, then all the other things, chicken or whatever, the occasional dessert. I always think about the vegetables for the microbiome for the reasons I've already said, a diverse diet for them means better health for me.

David: It's very good we've been sort of eating that way, and shows up in terms of lower blood pressure and cholesterol levels. It's been very good for us.

Anne: Just like in Japan and everywhere we have different vegetables through the seasons. And so right now in the fall, we have lots of Brussels sprouts. We just steam them and then have with a little bit of salt and pepper and olive oil. It's a little cabbage, a Brassica, they taste very different than a big cabbage. They will be part of our dinner tonight. I think the microbiome likes the seasonal eating too that comes with the different crops over the course of a year.

Aoi: Wow, you are a very good gardener and cook.

Fujii: Thank you very much for a long interview for you very much. Yeah, we are glad to talk with you. We are also looking forward to looking at new publication as well.

Anne: Yes, we are very excited to have just turned the manuscript for the new book into our publisher. It should be out sometime in 2022.


Seattle: 16:00-, Nov.16,2020 / Tokyo and Kyoto: 9:00-, Nov.17,2020, on Zoom

アン・ビクレー（Anne Biklé）
生物学者、環境プランナー、科学ライター。主な著書＝『土と内臓（The Hidden Half of Nature: The Microbial Roots of Life and Health）』（デイビッド・モントゴメリーと共著、W. W. Norton & Co., Inc.、2015／片岡夏実訳、築地書館、2016）など。

デイビッド・モントゴメリー（David R. Montgomery）
ワシントン大学地球宇宙科学科・地形学研究グループ教授。地質学者。主な著書＝『King of Fish: The Thousand─Year Run of Salmon』（Westview Press、2003）、『土の文明史──ローマ帝国、マヤ文明を滅ぼし、米国、中国を衰退させる土の話』（築地書館、2010）、『岩は嘘をつかない──地質学が読み解くノアの洪水と地球の歴史』（白揚社、2015）