Mid-Century Japanese Woodblock Print with Trees, Bulbs, and Giant Tuber

I believe I am correct in reading this terrific mid-century Japanese woodblock print as a portrayal of the strata of the earth. At top, branches of leaves and blossoms gracefully arching above the against the sky and clouds, then neat rows of evergreens delineating the horizon line. Below the earth, first a couple pf bulbs, maybe onions, and then buried deeper in the earth what I imagine is a giant tuber, or Imo--perhaps a gorgeous huge sweet potato! 

Executed in black and gray ink on a rice-type paper, with wonderful patterns throughout. This piece came from the estate of Renate Scheer Kalkofen (1935-2013), whose own work I've got listed separately. Very good condition, with a light center crease  and a tiny bit of light foxing at upper right. Paper size is 17 7/8" x 12 7/8". I am not certain of the artist, but it is signed with a chop at lower right.