Mary Agnes Yerkes (1886 - 1989)
Mary Agnes Yerkes was born in Oak Park, Illinois on August 9th, 1886. Her parents, Charles Sherman Yerkes and Mary Greenlees Yerkes, had moved to their N. Grove Ave. home a few years earlier from Ohio. She was the third child of four siblings; Reuben Archibald, Alice Agnew, and Charles Greenlees. Mary Agnes graduated from Oak Park and River Forest High School in 1906, and became an accomplished local artist. She studied at the Rockford College, the Academy of Fine Arts [where she also taught] and the School of the Chicago Art Institute, had special painting instruction under Wellington Reynolds, John W. Norton and Walter Marshall Clute, and participated in numerous exhibitions, including the exhibits of Chicago artists and of the American Water Color Society at the Art Institute from 1912-1915. 
Mary Agnes also had a two week showing at Grable’s art store on Oak Park Avenue during October, 1915, about which a local critic wrote: “Miss Yerkes’ work shows remarkable versatility in both subject and medium, and she is unusually successful in doing many things well. The pictures are in oil and pastel and watercolor, and their subjects range from figures to landscape and still life, and from the daintiest spring to drifting winter snows. Thru all of her pictures, however, runs the same gift of clear, joyous, exquisite color. She will be very famous some day for her sense of color, and also for her rare gift of imagination.” , 
Her father died in 1908 and her mother shortly thereafter commissioned a home from architect John S. Van Bergen, a protégé of Frank Lloyd Wright, in 1913. The “Mary Greenlees Residence” is an Oak Park Preservation Trust award recipient. The home was specifically designed with an upstairs art studio for Mary Agnes. Records at the Art Institute of her exhibitions and listings within Oak Park directories show Mary Agnes living at this 450 Iowa address from 1913-1919. Her mother lived with Mary Agnes until the end.
In 1917, she married Navy Commander Archibald Offley and had one child, Mary Yerkes Offley, born in 1918 and died at the age of 13. The married life of a navel officer found them transferred to several ports on the West Coast; San Diego, Vallejo and Long Beach, CA. among others. They finally took up permanent residence in San Mateo, CA. around 1941 where she lived till her death on July 29, 1989, a few days shy of her 103rd birthday.
Mary Agnes spent all of her adult life painting. With California as a base, she took frequent trips to paint her favorite subject matter, our national parks. She traveled and camped the entire American West. From Tucson to Alberta, Canada and from Yosemite Valley to Santa Fe, she found passion in nature, the love of art and its process. She painted, hooked rugs of her own design, and wove fabric on her loom for her own clothes and accessories. She kept a number of her own paintings, which to her represented fond memories and as a result never dispersed. They are now her legacy, as one of the great women painters of the American West.
Information provided by Craig H. Yerkes, grand nephew of the artist.
 Todd Ellis, Researcher, 2001, Wright Plus 2001 Project, “Mary Greenlees Residence”
 Oak Leaves, Oct 23, 1915