[VonBarb.]

What pursuivant said. Most of the crops in the picture would be completely out of place in a 1940s context, especially rapeseed. Wheat would also be much more widely represented, with some crops reaching maturity as soon as mid/late Spring. Generally speaking, there were also much more trees, bigger forest areas, and more snow until later in the year.
Some landscapes have changed quite dramatically since the 40s and it's hard to use modern pictures to get an idea of how thoses places looked like. Just Google Okinawa in Google Maps...

Cheers

Nico