Cedar Pollen Allergy and National Policy: The Tragedy of a National Illness Born from Post-War Reconstruction Ambition

When I contact my Japanese friends in spring, one phrase always comes up: "The pollen is so bad, I'm dying." News channels broadcast 'Today's Pollen Count' with grave seriousness every day, and the streets are filled with people equipped with dust-proof glasses and masks. The cause of all this commotion is cedar (sugi), but these trees didn't grow naturally.

Immediately after World War II, the Japanese government planted hundreds of millions of these trees as part of an artificial forestation effort to rebuild the country. Eighty years later, that decision has come back as a social problem that erodes the quality of life. If you delve into how this happened, you'll find a textbook example of environmental policy failure.

The Result of a Policy to 'Plant Gold' in the Mountains

After its defeat in 1945, Japan faced a severe timber shortage. With homes destroyed by war and mountains stripped bare for rebuilding and heating, Japan's forests were devastated. In the 1950s, the Japanese government actively promoted an expanded afforestation policy (拡大造林政策)to green the land and secure timber for construction.

The trees chosen by the government at this time were cedar and cypress. Cedar, in particular, grew incredibly fast and had straight trunks, making it excellent for construction materials. Under the slogan "Plant gold in the mountains!", Japanese people cut down native broadleaf trees and planted hundreds of millions of cedars in their place.

The problem arose when it was time to 'harvest' these trees. From the 1970s onwards, cheap imported timber entered the market, and rising labor costs in Japan led to a decline in the forestry industry. The planted cedars were left unharvested, and after more than 30 years, they entered their peak pollen production period.

It's Not Just an Itchy Nose

Cedar pollen is so small and light that it can travel hundreds of kilometers with just a breeze. Japan's unique basin topography and urban asphalt surfaces create the worst possible environment, allowing pollen to continuously circulate without decomposing.

It's not just an itchy nose. This phenomenon, which saps the concentration of the entire nation, can be considered one of the most serious environmental backlashes Japan is currently experiencing.

How to Change Already Planted Trees

As public dissatisfaction grew, the Japanese government belatedly began developing low-pollen cedar varieties and a project to replace existing cedars with new varieties. However, replacing billions of already planted trees is almost impossible.

The government mandates the use of domestic cedar for public buildings to boost timber consumption and has developed a system that uses AI to accurately predict pollen dispersion. They are even researching cedars that don't produce pollen at all using gene-editing technology. However, the pace of forest change cannot keep up with the suffering of the people.

Ultimately, Japan's cedar problem clearly demonstrates the consequences of prioritizing short-term gainsand ignoring ecological diversity. I believe it's a living textbook case that teaches the world how important environmental policy is.

For Travelers Visiting Japan in Spring

If you have pollen allergies, traveling to Honshu in March-April is honestly difficult. Fortunately, there are places in Japan where you don't have to worry about pollen. Hokkaidohas almost no cedar due to its climate, Okinawais subtropical, so cedar trees don't grow there at all. The Ogasawara Islandsare a 24-hour boat ride from Tokyo, but they are clean islands completely separated from the mainland.

If you must visit Honshu in spring: KF80 or higher mask is essential, get allergy medication prescribed before departure, wash hands and brush off clothes after going out. Checking if your accommodation has an air purifier can also help. If traveling in May or later, or in winter, is possible, that would be the most comfortable option.