September 1856
D. Ross of New York settled in Turtle Township (per garbled settlement list).
Rock CountyGrade A · 1 independent source
The evidence
“D. Ross New York Turtle September, 1856 1854 March, William H. Stark....”
1879-history-of-rock-county/13-rock-county-ch07-town-histories.md, PDF p. 524
Butterfield, C. W., et al. The History of Rock County, Wisconsin: its early settlement, growth, development, resources, etc. Chicago: Western Historical Company, 1879. Cornell University Library via the Internet Archive, archive.org/details/cu31924028871585.
Grade A: Found on a page of one of our sources
The printed page (PDF p. 524). The passage could not be located on the scan automatically.