Maynard Dixon
I went to see the Maynard Dixon show when it was at the Tucson Museum of Art. I was really struck by the simplicity and accuracy of his graphite and chalk drawings. He seemed very confident of his lines. The lack of photographic reference during that time meant that he practiced drawing from life.
His paintings had the same confident simplicity with close attention to composition and atmoshere and very little attention on detail or technique. His paintings made simple statements that we can all appreciate and learn from. You might enjoy reading Desert Dreams: The Art and Life of Maynard Dixon, Revised Edition