Some believers think the crown of thorns was made of this type of tumbleweed. His sample of pollen grains originated with Max Frei, who tape-lifted pollen grain samples from the shroud.
Frei's pollen grains have been controversial from the beginning.
For example, it is claimed to be the negative image of a crucifixion victim.
It is claimed to be the image of a man brutally beaten in a way which corresponds to the way Jesus is thought to have been treated.
(Another equally famous painting, also claimed to have miraculously appeared on a cloth, cropped up in Mexico in the 16th century, "Our Lady of Guadalupe.") The case for the forged shroud is made most forcefully by Joe Nickell in his Inquest On The Shroud Of Turin, which was written in collaboration with a panel of scientific and technical experts.
The author claims that historical, iconographic, pathological, physical, and chemical evidence points to its inauthenticity.
The shroud is a 14th century painting, not a 2000-year-old cloth with Jesus's image.
Mc Crone's theory is that "a male model was daubed with paint and wrapped in the sheet to create the shadowy figure of Jesus." The model was covered in red ochre, "a pigment found in earth and widely used in Italy during the Middle Ages, and pressed his forehead, cheekbones and other parts of his head and body on to the linen to create the image that exists today.
He claims this combination is found only around Jerusalem.
However, the floral images they see are hidden in mottled stains much the way the image of Jesus is hidden in a tortilla or the image of Mary is hidden in the bark of a tree.