Background artists didn’t tend to get credited on cartoons until the mid-1940s. So it’s only a wild guess that Fred Brunish provided the backgrounds for the cartoon with the first appearance of Woody Woodpecker, “Knock Knock” (1940). I don’t know when Willie Pogany left the studio. The blend of colours and detail is terrific.
Animation credits go to Alex Lovy and Frank Tipper, though someone may be able to tell me if La Verne Harding and Les Kline worked on this as well.