The 4-cent stamp honoring the Fifth World Forestry Congress was issued on August 29, 1960, through the Seattle, Washington, post office. The event took place from August 29, 1960, to September 10, 1960, in Seattle.
The stamp was printed by the rotary process, electric-eye perforated, and issued in panes of fifty stamps each. An initial printing of 120 million stamps was authorized.
Postal Bulletin (July 28, 1960).