Fossil Pine Pollen and Full‐Glacial Vegetation in Southeastern North Carolina
1964
A reassessment of the difficulties inherent in size—frequency identification of pollen indicates that the reliability of the method is of low order. Accurate identifications assume: (1) Adequate data on size variation for all relevant extant species; (2) a standardized method of preparation for all modern samples; (3) use of mounting medium in which size is stabilized (not glycerine or glycerine—jelly); (4) preparation of all samples from a given fossil profile by an identical technique (not necessarily the same as that employed for modern material); (5)cognizance of the fact that size of modern and fossil grains cannot be compared directly and that the size changes may occur as a function of sediment type within a profile; and (6) presentation of size—frequency curves for the fossil material. New Pollen size measurements for the 13 eastern pines indicate that no single species can be identified on a size—frequency basis. The mode for small pine grains described by Frey from the full—glacial portion (M Zone) of the Singletary Lake profile could have been contributed to by either jack pine or red pine (or both). These data and new pollen analyses from the M Zone sediments suggest that the dominant full—glacial forest type in the region consisted of widely spaced pines (jack and/or red pine) associated with heliophytic herbs and shrubs (Artemisia, Polygonella, Plantago, Ambrosia, caryophylls, and chenopods). Boreal elements (Picea, Abies, Schizeae pusilla, Sanguisorba canadensis, Lycopodium annotinum, L. lucidulum) may have occurred on more mesic sites surrounding the lakes or on the poorly drained inter—Bay regions.
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