Vincent van Gogh, The Harvest (1888), Pen and Brown Ink over graphite. Courtesy of the National Gallery of Art. Washington, D.C. at: http://www.nga.gov/.
In Mark Getlein's Living with Art - Chapter Six, the medium that applies to Van Gogh's "The Harvest" is drawing on paper. Van Gogh used a "quill pen which is made from the tail or wing feathers of the goose, swan, and crow that has the tip of the feather cut with a penknife to a fine or broad point" to employ his style or, technique of dynamic broad brushstrokes. This technique seems to have created a rough field texture in the wheat field and a smooth surface for the road that draws attention up the center toward the town in this massive composition. Van Gogh uses this technique in a variety of different sizes of straight lines build value or a degree of lightness to this landscape in linear perspective to the distant foreground which is further away in an area thickly colored with brown ink. (courtesy: www.metamuseum.org/explore/van_gogh/glossary.html) Drawing is a personal expression and considered intimate and many artists had no intention of considering a drawing a final work. Perhaps, Van Gogh use of "direct expression" -an artistic term used to describe a glimpse into the creative process- "from brain to hand" in familiar scene the art theme of daily life: as he drew in the here and now in many other similar wheat field compositions. However, the method of drawing seen here is more defined as symmetrically balanced supported by a quality that creates a strong sense of unity among the elements used within this naturalistic piece.
Vincent van Gogh, "The Emperor Moth" (May 1889), Oil on canvas. Van Gogh Museum, Amsterdam. (Vincent van Gogh Foundation). Courtesy of the National Gallery of Art, Washington, D.C. at: www.nga.gov.
In conclusion, oil paint on canvas medium enhances the overall visual impact of "The Emperor Moth" drawing attention to the colorful and exciting titled image, in contrast to somber image in "The Harvest" landscape drawing. While using different mediums in his works, Van Gogh employs his signature styles in a somber and a lively expression of the here and now themes of art in daily life and nature in both compositions.