Tephra layers form important chronostratigraphic marker horizons within the Wisconsinan loess-paleosol stratigraphy of the Palouse, Washington State. This paper details the presence of disseminated glass shards of the Trego Hot Springs tephra that has not previously been recognized within the Palouse or environs. The tephra provides additional chronological control for the regional Late Wisconsinan stratigraphy and raises the possibility of correlating the paleoclimatic proxy record contained within the Palouse to those of lake sequences in Oregon, California, and Nevada.