The Cullars Rotation is a historic sie in Auburn Alabama. It is the home to a soil fertility experiment conducted by the Auburn University. It was started in 1911, making it the oldest ongoing cotton fertility experiment in the country. The site is also the oldest experiment facility of the sort in the region, as well as the second oldest cotton experiment in the planet that is still ongoing today.

The Cullars Rotation experiment started when the state legislature decided to sponsor a study that could learn of the long term effects of fertilization on a rotation of corn, wheat, soybeans, and cotton that spans of three years. The experiment is still ongoing, although, the public isn?t allowed to enter the site. You can get a glimpse of it, however, in the neighboring facility inside the Auburn University campus known as the Jule Collins Smith Museum of Fine Art.