Rocks recovered from the drilling of an injection well on Pine Island provide clues to the nature of the earliest land plants so far discovered in Florida.

photo of Pollen of the Gentian family
Pollen of the Gentian family of flowering plants points to insect pollination and represents the earliest land plants recovered from Florida. Photo by D. Jarzen

By identifying the pollen and spores contained in the rocks, and identifying the parent plants that produced the pollen, scientists at the Florida Museum of Natural History and ENTRIX Corporation in Fort Myers demonstrated that Pine Island had land plants growing on the island about 35 million years ago in the Eocene epoch.

Some of the pollen was identified as airborne, and could have traveled to Pine Island over great expanses of water. However—and of great significance— some pollen is related to plants that are pollinated by insects, and are not transported far at all. Contrary to earlier beliefs that Florida was submerged during the Eocene, there must have been land at or near the present site of Pine Island in order for the plants to have grown and the pollen to have entered the fossil record.

Similar studies of rocks from Levy and Citrus counties in Florida have also demonstrated that Florida was not submerged during the Eocene. But the pollen recovered from Pine Island clearly shows that the oldest land plants thus far discovered are from Pine Island. Together, the findings from Florida suggest perhaps a chain of islands from the mainland stretching into the Gulf of Mexico as do the Florida Keys today.


This article was taken from the Friends of the Randell Research Center Newsletter Vol 10, No. 1. March 2011.