Japan's Reforestation Problem: Leeches

Japan's leech invasion may be an unintended consequence of successful reforestation efforts combined with rural population declines.

1 minute read

September 10, 2007, 8:00 AM PDT

By Michael Dudley


"What to make of this leech fest?...Japan's remarkable reforestation record is hardly a new phenomenon. In fact, Japan has reforested itself twice -- once dating back to the 1600s, and again after World War II. Likewise, Japan's demographic woes have been a hot topic for years. Japan's population of 127 million has peaked, and some estimates predict the total will drop to 95 million by 2050.

The most dramatic decline is occurring in rural Japan where the few young people who are actually being born are abandoning the countryside for the city. Which means, according to Asahi Shimbun, that not only are local forests thriving, but that the buffer areas between inhabited regions and the forest are being neglected. The ensuing profusion of weedy growth attracts animals whose numbers are increasing because of hunting restrictions and warm winters. The leeches latch on to the beasties and go for a ride, looking for more fresh meat.

Japan's success at reforestation offers an encouraging model to the rest of the world. Likewise, its imminent population decline suggests that humanity isn't necessarily doomed to perish under the weight of its own numbers. But even so, as a metaphor for the kind of unexpected, and unwelcome, manifestations likely to result from human mismanagement of the world's natural resources, a plague of bloodsucking leeches is not too shabby."

Friday, September 7, 2007 in Salon

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Get top-rated, practical training

Aerial view of single-family homes with swimming pools in San Diego, California.

San Diego to Rescind Multi-Unit ADU Rule

The city wants to close a loophole that allowed developers to build apartment buildings on single-family lots as ADUs.

March 9, 2025 - Axios

Canadian flag in foreground with blurred Canadian Parliament building in background in Ottawa, Ontario, Canada.

Has President Trump Met His Match?

Doug Ford, the no-nonsense premier of Canada's most populous province, Ontario, is taking on Trump where it hurts — making American energy more expensive.

March 11, 2025 - Toronto Star

Close-up of green ULEZ sign in London, UK.

Study: London ULEZ Rapidly Cleaning up Air Pollution

Expanding the city’s ultra low-emission zone has resulted in dramatic drops in particle emissions in inner and outer London.

March 10, 2025 - Smart Cities World

Tents set up by unhoused people under freeway overpass in San Jose, California with American flag above them.

San Jose Mayor Takes Dual Approach to Unsheltered Homeless Population

In a commentary published in The Mercury News, Mayor Matt Mahan describes a shelter and law enforcement approach to ending targeted homeless encampments within Northern California's largest city.

March 14 - The Mercury News

Blue Atlanta streetcar on street in downtown Atlanta, Georgia.

Atlanta Changes Beltline Rail Plan

City officials say they are committed to building rail connections, but are nixing a prior plan to extend the streetcar network.

March 14 - Saporta Report

New York City city hall building.

Are Black Mayors Being Pushed Out of Office?

The mayors of New York, St. Louis, and Pittsburgh all stand to lose their seats in the coming weeks. They also all happen to be Black.

March 14 - Governing

Urban Design for Planners 1: Software Tools

This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.

Planning for Universal Design

Learn the tools for implementing Universal Design in planning regulations.