The Oregon Trail Association was founded in February 1922 to perpetuate the name of the "Old Oregon Trail" and to permanently mark it with the insignia of the ox team and the covered wagon.
In January 1926, in Washington, DC, the Oregon Trail
Memorial Association ("Association") [emphasis added] was formally established; Ezra Meeker, at the "seasoned" age of 95, was elected as the Association's president. Meeker had traversed the Trail as a young emigrant in 1852 and also in the early 20th century to promote the Trail and raise funds for its preservation. IMO, he was a "natural" selection as the Association's first president.
James Earle Fraser and his wife,
Laura Gardin Fraser, were commissioned by the Association to create the designs for the now-beloved Oregon Trail Memorial Half Dollar. A dateless version of the coin's design was used for the trail markers produced/distributed by the Association.
An alternate design was also created for the Association by the husband-and-wife team; it served as the Association's emblem/logo.
The linkage between the the designs of the Association emblem/logo version and the coin version is very apparent - they share the ox-driven wagon element - though there are obvious differences. On the emblem/logo version, gone from the background is the large, setting sun with its long emanating rays, replaced by mountain peaks (presumably, a small section of the Rocky Mountains). No date is found on the emblem, "ASSOCIATION" has been added and there are three five-pointed stars at the lower rim vs. a date (the coin employs five stars in its design below "OREGON TRAIL MEMORIAL"). No doubt an attractive design, but difficult to judge its overall merits through lenses accustomed to the designs of the half dollar.
Here are a couple of examples of the Association emblem/logo:
Oregon Memorial Trail Association Emblem/LogoFrom a 1930 booklet titled
Oregon Trail: A Plan to Honor the Pioneers:
An envelope postmarked in 1937 (I've covered the addressee and address) showing the emblem/logo vs. return address:
1926 Oregon Trail Memorial Half Dollar

For more of my stories about commemorative coins and medals, including other Oregon Trail stories, see:
Commems Collection.