Zea pollen grains, presumably maize because of their large size, first appear in a stratigraphic core at 865 cm below the lake surface (approximately 220 cm below the lake bed) (Watts and Bradbury 1982:60-61). No Zea pollen was found deeper than this level. A radiocarbon sample (QL-1342) was taken just below this depth, between 878 and 881 cm, so it is slightly older than the earliest maize pollen.