POLLEN AND SPORES — LEOPOLD AND SOOTT 317 



especially dependent upon correlative evidence from associated fos- 

 sils and from the physical character of the deposit. 



An example of the use of fossil pollen in reconstruction of a pre- 

 historic human environment is the sequence described by Godwin 

 (1948) for Shapwick Heath (bog), Somerset, England, where inter- 

 esting Iron and Bronze Age artifacts have been discovered. The 

 pollen, from a series of sediment samples taken at close intervals be- 

 low, at, and above the levels where artifacts were found, documented 

 a series of changes in the vegetation that revealed the nature of the 

 human cultures. Interpretation of the resultant pollen diagram was 

 based upon changes in the kinds and numbers of weed, forb, and 

 agricultural plant pollen present in the section. 



Less than half a meter below the bog surface were discovered the 

 well-preserved remains of a log trackway (Westhay trackway) con- 

 structed of longitudinally laid birch timbers and small, more or less 

 vertical stakes pinning these in place ; the birch timbers showed clear 

 ax cuts that by their nature could not have been made by a modern 

 ax, but were characteristic of the marks left by certain ax types used 

 in the late Bronze Age. Associated with the trackway timbers was 

 a spearhead that was of late Bronze Age. 



At other locations in Shapwick Heath, commercial peat-mining 

 operations revealed no less than five food caches buried below the 

 modern surface of the bog, and these are datable to the Romano- 

 British culture by the coins contained in them. At other localities, 

 a scabbard (La Tene scabbard), of late Iron Age, and also a primitive 

 boat, 18 feet long, were discovered under several feet of peat. The 

 archeological age of the boat is not certain, but the plant species pres- 

 ent indicate that open water has been scarce or absent on Shapwick 

 Heath since the time of the Westhay trackway. 



In sediments just below the oldest of these artifacts (the timbers 

 of the Westhay trackway), weed, cereal, and forb pollen types are 

 present, and in sediments above the trackway believed to be con- 

 temporaneous with the late Iron Age, these same pollen types are 

 especially numerous. 



Pollen representing weeds and f orbs in Shapwick Heath sediments 

 include Rumex, Artemisia (sage), members of the daisy and lamb's- 

 quarters families, and plantains. The most significant plantain 

 species is Plantago lanceolata which elsewhere in European post- 

 glacial sequences has been found only in sediments younger than 

 Neolithic Age. It is a well-established fact that this plantain species 

 has proliferated in Europe only in the last few thousand years, and 

 that it is probably a weed associated with human disturbance of the 

 vegetation. The cereals present include grasses and members of the 

 barley group, which are difficult to identify to genus by their pollen. 



