A Pollen Profile from the Grassland Province

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Science  22 Dec 1961:
Vol. 134, Issue 3495, pp. 2038-2040
DOI: 10.1126/science.134.3495.2038-a


Hackberry Lake near Valentine, Nebraska, has deposited about 5 meters of sediment in little more than 5000 years. Its mass pollen spectrum shows over 50 percent grass and about 12 percent tree pollen, but the mass spectrum for the lowest meter shows less than 30 percent grass and over 20 percent tree pollen. This suggests a cooler and more humid climate at inception of the lake than later, and raises interesting questions requiring further research.