In the 1838 account Smith said that this vision occurred "on the morning of a beautiful, clear day, early in the spring of eighteen hundred and twenty." Two Latter-day Saints, researching weather reports and maple sugar production records, argue in a non-peer-reviewed magazine article that the most likely exact date for the First Vision was Palm Sunday, March 26, 1820. Mark Staker, an expert on the sacred grove site, states that early spring would be "sometime in most likely March, April, or the beginning weeks of May."