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

Use Code 25for25 at checkout for 25% off an annual plan!

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

June 4, 2025 - Diana Ionescu

White and yellow DART light rail train in Dallas, Texas with brick building in background.

DARTSpace Platform Streamlines Dallas TOD Application Process

The Dallas transit agency hopes a shorter permitting timeline will boost transit-oriented development around rail stations.

May 28, 2025 - Mass Transit

Metrorail train pulling into newly opened subterranean station in Washington, D.C. with crowd on platform taking photos.

Congressman Proposes Bill to Rename DC Metro “Trump Train”

The Make Autorail Great Again Act would withhold federal funding to the system until the Washington Metropolitan Area Transit Authority (WMATA), rebrands as the Washington Metropolitan Authority for Greater Access (WMAGA).

June 2, 2025 - The Hill

Worker in hard hat stands in front of oil pipeline under construction with yellow heavy equipment.

Supreme Court Ruling in Pipeline Case Guts Federal Environmental Law

The decision limits the scope of a federal law that mandates extensive environmental impact reviews of energy, infrastructure, and transportation projects.

5 hours ago - NPR

White, yellow, and blue Dallas Streetcar at station in downtown Dallas, Texas.

Texas State Bills to Defund Dallas Transit Die

DART would have seen a 30% service cut, $230M annual losses had the bills survived.

6 hours ago - Plano Star Courier

Collage of three photos of Team England cricket players taking green Lime bike share bikes to a game.

Bikeshare for the Win: Team Pedals to London Cricket Match, Beats Rivals Stuck in Traffic

While their opponents sat in gridlock, England's national cricket team hopped Lime bikes, riding to a 3-0 victory.

7 hours ago - The Straits Times

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.