Dear Lou, Do you know where I can obtain Lycopodium marker tablets? I received an email letter from Bjorn Berglund saying that he is no longer making them owing to a problem with the manufacturer. He implied that he had no schedule for further production. I have a few left but will need another batch in about a month. Would you put an ad in the newsletter for me asking anyone who might have some extra tablets to e-mail me?
I have received at least a half dozen inquiries during the last few months from people needing a source for spore marker tablets. Back in 1973, I arranged for Jens Stockmarr to produce a batch of Eucalyptus tablets for a group of palynologists here in the U.S. I am down to my last bottle of that batch. I still have a few bottles of Stockmarr's original batch of Lycopodium tablets, and I treat those like gold.
This is really a very serious problem to my way of thinking. A well made marker-grain tablet is surely the most efficient way to introduce a marker to a pollen sample. I have heard it said that pipetting markers is just as good, but that ignores the risk that the mean and standard deviation of pipetted stock fluids can change with time and operator. I have also heard palynologists say they do not care about tablets because they use micro-spheres or glass beads as markers. But because these cannot be added until after the chemical processing, the major value of adding a durable spore before processing to negate the effects of processing loss is no longer available.
I might add that I find a well-darkened Lycopodium spore to be the best for strength and visibility. Some of the Eucalyptus grains in the batch I had made were a little too faint to be recognized easily. I might also add that it is good not to have too many spores in a tablet. If you need to add several tablets to get enough markers, you automatically decrease the variance of the spike with respect to its mean.
Does anyone have an answer? Does anyone know of a friendly academic pharmaceutical engineering department who might like to have a student project? Let me know, and I will try to enlist another spore-buyers' consortium.