Fritz Baumgarten was a German children’s book illustrator active in the early to mid part of the 20th century.
He illustrated numerous books, primarily in Germany, working in a nicely finessed combination of ink and watercolor.
Baumgarten had a knack for blending the commonplace with the fantastic, putting his elf-like characters and anthropomorphized creatures into scenes of activities that might otherwise seem quite ordinary.
Many of his portrayals of the forest floor are nicely naturalistic.
I haven’t been able to find many sources for his images, but I’ve included links to a few, below. I’ll also provide a link to a Google image search, with the size filter set to “large”, and some books available on Amazon (most appear to be German language editions).