Change of Stock/Seed/Conditions

Cooper: Selection vs Change of seed (1799)

MacPhail: Change of Potato Seed (1819)

Deane: Change of Seeds (1822)

SPR: Change of Seed (1835)

FR: Change of Seeds (1838)

Thaer: Change of Seed (1856)

Darwin: Change of Conditions (1867)

NBA: Change of Seeds (1876)

Beal: Seeds (1878)

Herr: Change of Conditions (1888)

Corbett (1902): For a specific example of this, nothing could be more conclusive than the results shown by New York grown potatoes, given one season's outing in Maine, for, when brought back to New York the next year, they retained their Maine tendency towards increased vigor and yield.