The late Dr. Max Frei, a botanist and Swiss criminologist took sticky tape samples of particulate matter on the surface of the Shroud in 1973 and again in 1978 as a member of the STURP team. The procedure was simple. He took transparent adhesive tape and rubbed it on the surface so that loose particles stuck to the tape for later microscopic and chemical analysis. Among the particles collected on the tape were dust, pollen, plant and insect parts, blood from the blood stains on the Shroud, and loose fibrils of the fabric.

Frei was severely criticized in some quarters for his sticky tape methods. Others on the STURP team had used a specialized tool to apply a minimum, exact, and uniform pressure with a high grade Mylar tape. As historian Ian Wilson tells it, "Frei, Columbo-style, took out of his pocket the sort of Scotch tape dispenser that can be purchased in any supermarket and proceeded to press pieces from this into the Shroud with what seemed quite inordinate vigor." As it turned out, Frei was right. The STURP sticky tape picked up only one pollen sample and the special Mylar tape proved less than satisfactory for microscopic work. Frei's tape picked up hundreds of  deep-seated pollen spores along with other particles that have been examined extensively by many researchers. 

Before his death in 1983, Frei had identified pollen spores of 58 different plants, many that originate only in and around Jerusalem and areas of the middle east that include the ancient cities of Constantinople and Edessa. His finding, however, were not without controversy. Some members of STURP were not happy with methods. Other critics suggested that the pollens could have been carried by winds or birds to France or Italy, and there have settled on the surface. This notion of transported pollen has since been shown to be scientifically implausible, if not totally impossible. Frei's samples have proven invaluable to many and his work with pollen has since been confirmed.

The famous and eminent archeologist William Meacham sided with Frei and endorsed his findings calling the doubts of critics "unreasonable." In August of 1983 he wrote:

The pollen is another case of empirical data subjected to unreasonable doubt. Frei's pollen evidence does indicate a Middle Eastern origin for the cloth, which is not too surprising, as several other linen "shrouds" were brought back from the Crusades as relics..as a marker, percentages would be useful in determining the immediate environment represented by a deposit but not at all in proving that certain types are intrusive. The presence on the Shroud of a wide variety of Palestinian and Anatolian species is ipso facto evidence of an exposure to air in those regions, unless a similar presence can be documented in Holocene pollen deposits or on other medieval artifacts in France or Italy. It may be...that few STURP members give the pollen data any credence, but this does not detract in the least from the hard evidence Frei's work has revealed, especially in the identification of halophytes found almost exclusively around the Dead Sea. Riggi (1981), a member of STURP, has reported preliminary findings of Shroud pollen and minute animal forms "extremely similar in their aspects and dimensions" to those from Egyptian burial fabrics.

It was up to Dr. Avinoam Danin, a botany professor at the Hebrew University of Jerusalem and Dr. Uri Baruch, a pollen specialist at the Israel Antiquities Authority, to confirm and expand on Frei's work. In a recent conference of the Missouri Botanical Society in St Louis, Missouri, Danin, speaking about the pollen evidence and floral images found on the Shroud, reported that "In the light of our findings, it is highly probable that the shroud did in fact come from this part [the Jerusalem area] of the world." 

Dr. Avinoam Danin, confirmed 22 of the plant images identified by Dr. Whanger and Sheuermann. Of the remaining six identifications Sheuermann has expressed confidence that 3 are probably correct and 3 possibly correct.