Very nice image! Do you know if anyone has ever done x-ray
microanalysis across the section (or a similar section)?? That would
tell you if there were different elements preserved in different parts
of the root. I ask because I used to do this sort of thing on roots of
living plants (see my web site below for details). A lot of monocots
deposit Si to very high concentrations in the walls of the endodermis,
just outside the stele, and this and other elemental differences MIGHT
still be apparent!
Best Wishes,
Martin

Dr Martin J. Hodson,
Principal Lecturer in Environmental Biology,
School of Biological and Molecular Sciences,
Oxford Brookes University,
Gipsy Lane, Headington,
Oxford, OX3 0BP, UK

Tel.: ++44 (0)1865 483954
Fax: ++44 (0)1865 483242
Email:
Web: http://www.hodsons.org/MartinHodson/