AIC's 47th Annual Meeting

Both flax and hemp are the earliest fiber crops cultivated for textile production such as cloth and cordage. Archaeological findings of these two fibers are very common. To distinguish between the two, however, is often difficult because flax and hemp have very similar fiber morphology. Fiber identification is usually focused on fiber morphology alone without searching for other clues related to the fiber plant. Although their fibers look very similar, flax and hemp have very different and recognizable stem anatomies under the microscope, including their epidermis structures, fiber bundle formations of either primary or secondary growth, sizes of vessel elements, and crystals. The fiber identification approach applied in this study, holistic in nature, considered and investigated all these possible evidences towards the identification of six archaeological textile fragments. Reference flax and hemp stems were also examined for comparison. A light microscope with a digital camera was used to collect digital images. To obtain possible epidermis fragments and other tissue elements, it was often necessary to rub the sample either between slide and cover glass or to collect sample dust after rubbing the sample. Using image processing software, dimensions of fibers and plant tissue cells were measured to obtain quantitative date as part of the holistic investigation. As reported in the literature, trichomes or hairs were absent from the reference flax stem but very prominent on hemp stem. These trichomes are long unicellular hairs with base rings surrounded by epidermis cells. In contrast, stomata were a feature of flax epidermis. Flax and hemp stem also differs in phloem fiber bundle development that hemp stem contains very fine yet closely packed secondary phloem fiber bundles. Hemp fiber width distribution has a much larger range (8-67 µm) than that of flax (11-32 µm). Furthermore, hemp has wide pitted vessels (