FAQ's

Q. Why would I want to do pollen, phytolith, or macrofloral analysis?

A. This is a complex question. The answers will be short, so please read further in the rest of our website about the paleoenvironment and subsistence. Pollen and phytolith analysis can provide information concerning local and regional vegetation useful in reconstruction past vegetation in the vicinity of your site and interpreting paleoenvironmental conditions. Only when you understand the ecosystem in which people live can you interpret their behavior through the archaeological record. Therefore, stratigraphic pollen and phytolith analysis contribute to your overall understanding of the ecosystem in which people lived.

People ate a variety of plants and animals throughout the past. Many of these plants are represented in the pollen, phytolith, starch, and macrofloral records. Analyses of these various remains are not redundant. They do not simply provide more of the same type of information. Some plants are well represented in the pollen record when processed, but not either the phytolith or the macrofloral records. The same can be said of each of these types of remains. As an example, beans might leave behind phytoliths from the pods and hila in the macrofloral record, but would rarely leave behind pollen. Chewing yucca quids would introduce calcium oxalates, observed as part of the phytolith from tooth calculus. In addition, calcium oxalates would be retained in the quids and would help identify the plants chewed. Grinding Cheno-am seeds usually leaves behind a pollen record, but not phytoliths because Cheno-am seeds do not produce phytoliths. Parching Cheno-am seeds usually leaves a few charred seeds in hearths and similar features. Grinding grass seeds might leave behind both pollen and phytoliths on grinding surfaces. Processing roots in the umbel family might introduce both pollen and starch. Using wild onions would introduce pollen if the onions were dug while the plants were flowering, which is an aid to identifying the food being collected. Wild onions produce no phytoliths and very few starches. These are but a few examples of foods represented in the archaeobotanic record. Recovery of remains is directly related to production of pollen, phytoliths, starch, and macrofloral remains that might be preserved, given specific processing techniques.

Q.Do you have a specific submission form?

A. Yes, here. The important information is: number of samples, what type of analysis, list of samples, depth (please be consistent: below surface, below datum, or above base of feature). The use of our form is not required, but the information it asks for is necessary for analysis.

Features:

Q. Should I collect my feature samples from the upper part of the deposit, as soon as I notice the stain, so that I don’t forget?

A. No, that is the post-occupational portion of the fill and in most features has no relationship with the use of the feature. Samples from features should be collected from fill expected to reflect use of the feature, such as the bottom or bottom and lower sides.

Groundstone:

Q. Can we sample the dirt under a groundstone to identify what was ground?

A. It is really best to wash the groundstone to identify use of the tool. Evidence of plant processing is usually diluted in the sediment samples. Control samples should be collected for comparison with the groundstone wash. We prefer to wash the groundstone here, but have detailed instructions if it is not practical to send your groundstone to us. Remember, we want to examine what is embedded in the groundstone surface, not the dirt adhering to the surface, to interpret use of the tool.

Q. I hear pollen does not preserve on groundstone, so I want to do phytolith analysis.

A. Pollen preservation is usually not the problem. Some plant foods transport pollen and, thus, would leave pollen evidence of their processing on groundstone. Others produce phytoliths or are surrounded by plant parts that produce phytoliths, thus leaving a good signature for recovery. Still others are more likely to leave behind starches that are more easily recovered with the pollen processing technique than the phytolith processing technique. Therefore, evaluation of the appropriate analysis must take into consideration possible foods processed and which data base is most likely to yield results. For instance, when looking for evidence of Cheno-am processing, look in the pollen record because Cheno-am seeds and surrounding parts do not produce identifiable phytoliths although they do carry Cheno-am pollen.

Ceramic Vessels:

Q. Can we sample the fill of a vessel to identify original contents of the vessel?

A. No, usually not. It is best to wash the interior of the vessel to identify plant contents.

Preservation:

Q. There is no pollen in (Texas, Wyoming, New York, Israel, etc.) because Joe's pollen lab and hamburger shop could not recover it from my samples.

A. Joe uses the same pollen extraction technique that has been around for decades and was originally designed to extract pollen from peat samples. His technique, in general, is to chemically burn away almost everything but the pollen (he hopes) and then count the remainder. Admittedly, his technique works very well for peat but, quite frankly, the number of archaeological sites that are situated on peat are somewhat limited. We have developed a technique that is considerably more gentle on the pollen and allows us to recover interpretable pollen from depositional environments as harsh as a sand dune. In short, your sample very likely does contain interpretable pollen and, if anyone can find it, we will.

Q. Why does it take you so long to get the results back; other labs are quicker?

A. In general, the answer to this question is the same as why we can get pollen where other labs report that no pollen exists (our projects). If we were willing to chemically burn a sample until the pollen was unrecognizable and then tell you that there is no pollen in (Texas, Wyoming, New York, Israel), we could have your results back in a week or two also. Instead, we use a process that gently coaxes the pollen from your samples over the course of a month (difficult samples can take longer) and get samples that still contain countable pollen. After the processing is complete, there are still differences in our methods that take more time. Our gentle process produces samples that, when put on slides and counted, are considerably more cluttered that the typical palynologist would count. We count around microfragments of organic debris and slight amounts of silica that still remain after the extraction process. Dodging junk on a slide takes a little longer, but it gets results. Finally, once all of the slides have been counted and we are ready for the interpretation, we do a little more than just send you a table or a diagram and hope that you can figure out what it means. We take the time to explain our observations and provide you with the insights that we have had about your project. We put our education and experience to work for you.