It has been estimated that one in ten emigrants died during the crossing. Most of these graves were hastily-dug because few emigrants had the time to mark the graves of the deceased.
In most cases, graves were marked with little more than a simple wooden board. Nevertheless, some emigrants fashioned more elaborate markers from the materials at hand such as native rocks or, in one notable instance, a wagon rim. A number of these emigrant graves can still be found along the trails and through the dedicated research of some OCTA volunteers, the history of the deceased has been reconstructed and markers have been placed.
Much of this research was documented in Randy Brown and Reg Duffin, Graves and Sites on the Oregon and California Trails, printed by OCTA in 1991, with a second edition in 1998.
In the past 10 years, more research has been conducted on some of these graves since OCTA markers were first placed. Many updates are for graves located in Wyoming, and can be found online as a project of the Wyoming State Historical Society.