This stamp from New Zealand, issued in 1960, shows a de Havilland Beaver spraying crops. I am not sure why it was issued, but I do know that at one point in its production, plans to license and build the type in New Zealand were proposed and, a Royal New Zealand Air Force Beaver supported Sir Edmund Hillary’s expedition to the South Pole.
The DHC-2 Beaver is a single-engined, high-wing, propeller-driven, STOL aircraft developed by de Havilland Canada, and is primarily known as a bush plane. It is used for cargo and passenger hauling, aerial application (crop dusting and aerial top-dressing), and has been widely adopted by armed forces as a utility aircraft. Over 1,600 Beavers were produced until 1967 when the original line shut down.
Sadly, as with most of the stamps I am finding in this old album I am going through, it is in pretty poor condition, and with little to no catalogue value, but I hope nice to see :-)