Pyrus ussuriensis, Ussurian pear, Manchurian pear
North Korea issued a series of six stamps named WILD FLOWERS in 1966.
Since you asked about the name, I looked it up. This pear tree is named after the Ussuri river which flows in far eastern Russia and the south east region of North east China.
Not having any photos of this tree and not finding any reference to it in
THE MEDITERRANEAN GARDEN I decided to go for a relative
Pyrus calleryana. The three photos I have of this tree were taken in a newish park in Madrid a few years ago. We were lucky to be there at blossom time .
Pyrus calleryana is mentioned in AGM 2018 - THE POST - AGM TRIP
TO VALENCIA by Valerie Whittington
THE MEDITERRANEAN GARDEN number 95, January 2019.