“Even plants that appear peaceful actually live in fierce battles.”
A guide to the wondrous world of plants we never knew existed.
A record of a botanist's fascinating intellectual explorations

Unlike animals, the seemingly static and passive world of plants—is it truly as peaceful as it appears? The author, a leading Japanese botanist and doctor of agricultural science, begins this book by revealing, through his extensive research and profound insight into plants, that "even seemingly peaceful plants actually live in fierce struggle, and that this is the truth of the natural world."
When it was published in Japan, "Fighting Plants" received attention with reviews such as "a book that changed our indifferent view of plants" and "a book that allows us to discover aspects of the lives of plants that we had previously overlooked."
This fascinating botany book, like a drama or documentary, shows the surprising strategies and tactics that plants employ in their struggles with everything around them, from the environment and pathogens to insects, animals, and humans, in the natural world, an arena for survival.


It vividly depicts the struggles of plants, often considered the 'weak', against various opponents for survival.
Plants employ a variety of survival strategies, including deceiving, exploiting, betraying, and ultimately forming alliances with their enemies.
Some plants, such as pine and walnut trees, engage in an invisible chemical warfare that inhibits the growth of surrounding plants with substances released from their roots for their own growth. Other plants employ ants as bodyguards to protect themselves from pest attacks, and plant cells even resort to self-destruction as a last resort to prevent the spread of pathogens.


As the review suggests, "I would recommend this to my children to learn how difficult life is," the lives of plants are dynamic, much like a glimpse into human history.
You will be amazed and fascinated by the fact that immobile plants can survive and thrive in their own place, achieving success and balance.

Plants that cannot survive without sunlight compete with each other by spreading their leaves to receive sunlight.
Since all plants spread their leaves to receive sunlight, they must occupy a higher position than other plants to get more sunlight.
In this way, plants grow upwards while competing with each other.
Even if a plant tries to grow faster than other plants, it is difficult for it to grow exceptionally because its competitors are also growing at the same rate.
Since any plant is trying to grow as quickly as possible, it appears that all plants grow the same, like measuring the height of an acorn.
This is the phenomenon of 'just enough height'.
Even though the newly sprouted leaves spread their blades upwards, if the leaves grow thickly, the lower part becomes shaded and cannot receive sunlight.
Then the leaves at the bottom lose their function and fall off.
The situation is that only the leaves on top are spreading out.
When you enter the forest, the leaves are gathered only at the top, as if covered by a roof.
The leaves at the bottom fell off because they didn't get enough sunlight.
This appearance of leaves gathered only at the top is called a tree crown or grass crown.
If you look up from beneath the forest, you can see that the various leaves are intertwined to form a crown, like a jigsaw puzzle.
In this way, plants form a forest by competing for space and surrounding sunlight.
---From "The Fierce Competition Surrounding Sunlight"

Some plants are more hospitable and accept ants, trying to win them over.
Surprisingly, the plant attracts ants by providing not only food but also a home for the ant family to live in.
These plants, called 'ant plants', create spaces within their branches and allow ants to live there.
Of course, the food to feed the ants is also luxurious.
It provides ants with all nutrients, including sugars such as honey, as well as proteins and lipids.
Thanks to this, ants can live on this plant.
Instead, ants protect the plants from insects such as caterpillars that try to eat the leaves.
Unfortunately, in areas with cold winters, ants cannot remain in trees year-round, as they must nest underground to overwinter.
It is unlikely that any plants will appear that provide habitat for ants.
In tropical regions where there is no need to worry about overwintering, plants belonging to various families, such as the Pepper family, the Nettle family, the Leguminosae family, the Euphorbiaceae family, the Passionaceae family, the Clematis family, the Rubus chinensis family, and the Palm family, have evolved to coexist with ants in a similar system.
The tropical ants that I hired while begging for the plants to come to me are relieved to finally get the home they longed for.
Even when humans approach the plant, the ants show hostility and attack.
What a dependable bodyguard!
---From "Hiring a Security Guard"

When the fruit ripens, it turns red.
For example, fruits that ripen on trees, such as apples, peaches, persimmons, tangerines, and grapes, often have a reddish color, such as red, yellow, pink, or purple.
Fruits dyed red like this stand out.
The 'stop' signal was set to 'red' so that it could be seen from a distance.
Red light, which has a long wavelength, has the property of traveling farther than other colors of light.
That is why the fruit is chosen to be red so that it can be easily recognized from a distance.
Also, since plants are green, red, the opposite color of green, is especially noticeable.
The unripe fruits are green like the leaves and are not easily visible.
Also, it tastes bitter rather than sweet.
This is to protect the fruit by accumulating bitter substances, as it would be difficult if the seeds were eaten while they were still unripe.
For example, tannins contained in bitter persimmons and momordicin and charantin contained in unripe green persimmons are substances used to preserve the fruit.
These fruits eventually become sweet as the seeds ripen, removing bitter substances and accumulating sugars.
Only after it has become this delicious do the berries change color from green to red, signaling that they are in season.
'Don't eat the green one.' 'Eat the red one.' These are the signals of the fruit.
---From "Green Stops, Red Goes"

Plants prepare toxic substances, whether large or small, to protect themselves.
But humans love the toxic components of this plant.
For example, beverages that humans enjoy, such as green tea, black tea, coffee, cocoa, and herbal tea, have both stimulating and calming effects.
All of these are weakly toxic components of plants that function.
The scents of plants, such as incense and potpourri, also heal and restore people.
In forests, various plants produce substances that keep pests and pathogens away.
People take forest baths in forests like this.
Why does forest air, saturated with plant toxins and other toxic substances, have such beneficial effects on humans? One factor is the hormesis effect.
Hormesis is a Greek word meaning 'stimulus'.
The poisons found in drinks, spices, and plants abundant in forests are not strong enough to harm humans.
It only acts to the extent that it acts as a stimulant to humans.
That is, the human body enters a defense system to protect life when stimulated by a weak poison.
That tension activates our ability to live and energizes us.
There's a fine line between poison and medicine.
If you consume a small amount of poison, it can be a good stimulus to the human body and act as medicine.
In fact, humans use most of the toxins that plants accumulate to kill microorganisms and insects as medicinal ingredients in herbal medicines.

---From "Reviving Vitality with Weak Ingredients"