For a decade or so Park led a ceremony on that day and was photographed planting trees, often with his children. He and others made lofty speeches, such as when, in 1968, "Seoul Mayor Kim Hyun-ok...emphasized planting trees as a sacred task for the modernization of the Republic and this generation’s sublime duty for the welfare of our descendants."
Here are a few photos and cartoons drawn from the Korea Times:
Korea Times, April 6, 1968.
Korea Times, April 6, 1965.
Korea Times, April 5, 1967.
Korea Times, April 5, 1970.