Identification of waterlogged plant tissues

Individual tissues (as opposed to whole organs like fruits and seeds see Charred Seeds - Identification) may also be preserved in waterlogged sediments and require identification. These include tissues from stems, capsules and pods as well as cereal bran, epidermis fragments of leaves, twigs and fruits, and tissues which form part of fruits and seeds.

Some plant tissue can be identified at a macroscopic level because of their morphological details, shape or colour, for example different stem fragments, capsules and pods from cultural plants, apple/pear endocarps as well as epidermis fragments of mistletoe. Other remains can only be identified under the microscope at a much higher magnification, and so have to mounted on slides, for example cereal bran, tiny wood or leaf tissues, fruit epidermis of Rosaceae and mistletoes, partition walls of flax capsules, testa of pulses, epidermis of leek etc.

For the identification of some of the tissues, descriptions, pictures and manuals are available, but these will not be able to substitute working with an reference collection of modern stuff.

Identification key

Beneath a simple key for the identification of common plant tissues as well as some references are given. In section A. tissues are mentioned which have obvious features to recognise them under a low-powered stereo microscope with 10-50-fold magnification. They can be sorted already during the scanning and sorting process. The tissues in section B. do not have specific macroscopic features. They must be put on a slide with glycerine to analyse their cell structure under a microscope with 100-400-fold magnification.

References

• Dickson, C. (1989). The Roman army diet in Britain and Germany. In: Körber-Grohne, U. und Küster, H. (Eds.), Archäobotanik. Symposium der Universität Hohenheim (Stuttgart) vom 11.-16. Juli 1988. dissertationes Botanicae 133: 135-154.
• Körber-Grohne, U. (1967). Geobotanische Untersuchungen auf der Feddersen Wierde. In: Haarnagel, W. (ed.), Feddersen Wierde, Band I, Römisch-Germanische Kommission des Deutschen Archäologischen Instituts zu Frankfurt am Main und Niedersächsisches Landesinstitut für Marschen- und Wurtenforschung in Wilhelmshaven. Wiesbaden, 355 p.
• Körber-Grohne, U. (1981). Distinguishing prehistoric cereal grains of Triticum and Secale on the basis of their surface patterns using the scanning electron microscope. Journal of Archaeological Sciences 8: 197-204.
• Körber-Grohne. U. (1991). Bestimmungsschlüssel für subfossile Gramineen-Früchte. In: Probleme der Küstenforschung im südlichen Nordseegebiet 18 (Hildesheim 1991), 169 ff.
• Körber-Grohne, U. und Piening, U. (1980). Microstructure of the surfaces of the carbonized an non-carbonized grains of cereals as observed in scanning electron and light microscopes as an additional aid in determining prehistoric finding. Flora 170: 189-228.
• Tomlinson, P. (1991). Vegetative plant remains from waterlogged deposits identified at York. Renfrew, J.M. (ed.): New Light on Early Farming. Recent Developments in Palaeoethnobotany. Edinburgh, 109-119.
• Tomlinson, P. (1985). Use of vegetative remains in the identification of dyeplants from 9th-10th century AD deposits at York. Journal of Archaeological Science 12 (4), 269-285.