On “exotics”: invasive species?

Thank you indeed for all the support you sent me since last week’s post! I’m doing my rehabilitation exercises now. A word of a person who’s done it: please do not break your bone, really.

So, I stayed in a hospital for operation on my broken wrist. i.e., I had time to read articles I piled up for quite some time. Among them, there was news from the Royal Horticultural Society about research on environment for bugs to thrive in Britain. In it, Steve Head, for the Wildlife Gardening Forum, wrote there are only 1625 “genuinely native plant species” in Britain. According to him, it’s because the British Isles were too soon separated from the Eurasian Continent after the recent Ice Age. As elsewhere, but from this level they are experiencing diminishing biodiversity. RHS is funding the research to identify the effects of imported gardening flora that could help stopping the decrease of bugs, and the other creatures who eat them, to maintain their biodiversity. The study is continuing; so far there emerges some possible findings, Head said. “Exotic” species can help insects especially when natives end their growing and flowering season, for sure. Though, the local species apparently do better to sustain the number of invertible. Probably reflecting the position of RHS in Britain, the article concluded ambivalently. They in the end says that imported exotic fauna can help increase UK’s biodiversity, and at the same time trade for native garden-worthy flowers could be promoted more … RHS also reported Britain has deer problem. The population of Reeve’s muntjac which was introduced in the early 20^th century from China is exploding in the 21^st century. As deer in Kanagawa, they devour the plants and damage barks. UK registers muntjac as an invasive alien species, but it seems to me they are still pondering what to do.

A very English scenery in Kew Garden.
To achieve this in Kanagawa,
we have to use tons of weed-killers,
i.e. reduce biodiversity.

Hmmmmmmmmmmmmm … According to Shuichi Kato, for the Ministry of Agriculture, Forestry, and Fishery of Japan, by the same measure, Japan has 5300 plants. So, from the start, our level of biodiversity is different from the UK, or Europe who are, it seems to me, leading the international dialogue about environment and trade … It would be tricky for us Japanese to talk about, say, international trade of fresh products and their effect on biodiversity in Japan. … Another article I found in my hospital bed was a reprint of a memo written in 1946 by Tomitaro Makino, the founding father of Japanese modern plant taxonomy. There, he told extinct plants in the downtown of Tokyo and Yokohama, and “exotics” in the same area where during the late 19^th to the early 20^th centuries he collected specimen. According to him, at the beginning of the 20^th century, Tokyo’s Marunouchi 丸の内 area where now many TOPIX100 companies have their HDQ had a substantial grass land with lots of native plants and occasional “exotics” coming from somewhere on earth. Having said that, he recalled Yokohama already had notable colonies of non-native plants like Euphorbia maculate L. or Juncus bufonius L. OK. Yokohama has been the major international port of Japan since 1854. Makino’s recollection should reflect this. Makino said already in the middle of the 20^th century, those places listed in the article were concreted and the native plants in his library for specimens were annihilated. And the “exotics” found in Yokohama and Tokyo some 50 years ago then were becoming common all over Japan. If adding exotics simply and peacefully to the existing 5300, the matter won’t be much problem … as RHS would expect for the UK gardens. If not, as Makino alluded, that could mean lesser biodiversity in Japan, and ultimately for the planet. Until 1854, Japan strictly closed its door to the outer world restricting the movement of goods and humans. Some 30 or so years later, sharp eyes of Dr. Makino have spotted the changes in plants. I fantasized in my hospital bed if Makino had had the same 21^st century knowledge and technology, Japan could have provided him and the world a perfect ground for scientific experiment to study the effect of international trade on environment. If such things had happened, how could his research have been reflected on the international dialogue for the sustainable development?

Actually last year’s venue for
the 2017 National Urban Greenery Fair 全国都市緑化フェア was the forest where Makino spotted
lots of alien Juncus bufonius L. and the others.
The place was very near to Niiharu Citizen Forest
and the keepers of Niiharu were furious for the City
who invited commercial garden designer
from far-away Kobe 神戸 to plant lots of “exotics” next door.
“What on earth do they think when we in Niiharu are busy
digging up invasive alien plants to sustain the biodiversity here!?”
“Of course, it’s for the business of (er, XXX) Seedling Co.
who has a strong connection with the powers-that-be.”
“Heck.”
In some way, the choice of this “beautiful” flower bed
might be fitting to this location.
The place where once the grandee of Japanese botany
collected the specimen of invasive plants was
covered almost entirely by alien flowers.
Oh, by the way,
“not-learning-from-experience” city will do the same
(but smaller scale) this spring at the same place.
People are gossiping this would be the last for this place
where the taxpayer money is siphoned to
the (above mentioned) seedling company.

For some time, I am thinking about the topic suggested by Fred Pearce in his “The New Wild.” This English suggestion certainly has a merit, especially for Britain (perhaps). Though … as a (novice) Japanese forest instructor I have reservation about applying his thinking to Japan. My first activity as a forest instructor was supposed to be guiding 11 years’ old from an elementary school of Tokyo in a forest of Yokohama. (Huh, I broke my wrist, and I could not meet these kids!) During the preparation, the teachers from the school asked us to teach them about “invasive species.” I found it very tricky. Yeah, say, Procambarus clarkia eat anything and drive native aquatic animals to extinction in Japanese streams especially near mega cities. They surely are contributing to the decrease of biodiversity in Yokohama and Kanagawa. They are almost at the top of the “Wanted” list of invasive alien species by national law and the groups of scholars. But they were brought here, or to be exact to an aquatic farm for edible frogs in Kamakura 鎌倉, in 1927 as meals for American bullfrogs. They did not ask to visit Japan. Can we teach kids “Hey, those are bad illegals to be exterminated”? Or can we confidently declare “Controlled introduction of exotic species can contribute to the enhancement of Japanese biodiversity” as Pearce or RHS may want to suggest for Britain? Procambarus clarkia in Japan is certainly the most apparent counter-evidence for the English argument. Even British bugs prefer natives to exotics for procreation, don’t they? And how about Chinese deer in Britain? … What would Makino say if he were around now? What might he suggest how to tell school kids about “exotics” in the forests of Japan?

I’ve found grey-capped green finches
when we previewed the forest
with the teachers from Tokyo.

The articles I read for this post are

Tomitaro Makino 牧野富太郎, A small reflection about the plants disappeared or multiplied around Tokyo 東京邊から消えた植物、殖えた植物等若干を述べて見る, in The Spirit of Plants: Tomitaro Makino 草木の精　牧野富太郎, National Museum of Nature and Science; Makino Botanical Garden of Kochi Prefecture; Museum of Bioresource Sciences for Nihon University, 1998.

Royal Horticultural Society. The Garden, January 2018 and February 2018.

Fred Pearce, The New Wild: why invasive species will be nature’s salvation, Beacon Press, 2015.

A caterpillar is trying to survive in a concrete jungle of Yokohama.