Laboratory preparation
1) Addition of Lycopodium tablets
When the trap contents are brought in from the field Lycopodium tablets are added so that pollen influx can be calculated. The number of tablets added per sample depends on the vegetation. The ratio between the number of added Lycopodium and the number of pollen counted in the pollen preparation must be such as to ensure statistical reliability (Stockmarr, 1971, 1973). In areas of low pollen producing vegetation 1 tablet may be enough while in others areas 5 may still not produce the desired ratio. For reasons of economy 5 tablets is regarded as the maximum number which it is realistic to add. A single tablet can be added directly to the trap contents, with larger numbers of tablets participants may wish to dissolve the Lycopodium tablets the day before in distilled water (not in HCl since this produces air bubbles inside the Lycopodium spores) and then add this to the trap contents.
Tablets can be obtained from:
Thomas Person,
Dept. of Quaternary Geology
University of Lund
Tornavägen 13
S-22363 LUND, Sweden.