Arbor Day in Korea getting too hot to plant trees

As the average temperature in spring in Korea has significantly increased over the past 70 years, March is becoming more suitable time for tree planting instead of the Korean Arbor Day, which falls on April 5.

On Thursday, Kweather, a private weather forecasting agency, analyzed the average temperatures on Arbor Day in six major cities (Seoul, Gangreung, Gwangju, Daegu, Busan, Jeju), and it has found that the temperatures rose by 1.8 to 3.5 degrees over the past 10 years compared to the 1940s when the Korean arbor day was designated.

During the 1940s, Jeju was the only city whose temperature rose above 10°C (10.1°C), but most cities except Seoul began to record temperatures higher than 10°C, starting in the 1970s. Among the six cities, Daegu showed the most dramatic surge in temperatures, with the mercury rising by 3.5°C over the past decade (12.4°C) compared to that in the 1940s.

The National Institute of Forest Science says 6.5°C is the most ideal temperature to plant trees. This year, Seoul and Daegu reached the optimal level for tree planting in daily average temperature on March 16, with Busan and Gwangju meeting the critical point on March 3.

“The traditional arbor day in Korea is no longer suitable for tree planting. We need to observe it as a symbolic occasion to raise awareness on the importance of trees and promote forestation,” says Professor Jeon Yeong-wu at Forest Resource Management Department of Kookmin University. “Recently, an increasing number of forestation experts are recommending to plant trees in March in the southern parts of the nation.”

임현석기자 lhs@donga.com