The topic of presence/absence of conifer stomata in lake sediment arose recently in discussion. The Quaternary discussion group provided the following references in response to my request; CAP members may find it useful.

Ammann, B., and L. Wick, 1993. Analysis of fossil stomata of conifers as indicators of the alpine treeline fluctuations during the Holocene. In: Oscillations of the Alpine and Polar Tree Limits in the Holocene, edited by B. Frenzel, pp. 175-185. Palaeoklimaforschung 9, Special Issue. G. Fischer Verlag, Stuttgart.

Clayden, S. L., L. C. Cwynar, and G. M. MacDonald, 1996. Stomate and pollen content of lake surface sediments from across the tree line on the Taimyr Peninsula, Siberia. Canadian Journal of Botany 74: 1009-1015.

Clayden, S. L., L. C. Cwynar, G. M. MacDonald, and A. A. Velichko, 1997. Holocene pollen and stomates from a forest-tundra site on the Taimyr peninsula, Siberia. Arctic and Alpine Research 29: 327-333.

Hansen, B. C. S., 1994. Conifer stomata analysis as a palaeoecological tool: an example from the Hudson Bay lowlands. Canadian Journal of Botany 73: 244-252.

Hansen, B. C. S., G. M. MacDonald, and K. A. Moser, 1996. Identifying the tundra-forest border in the stomate record: an analysis of lake surface samples from the Yellowknife area, Northwest Territories, Canada. Canadian Journal of Botany 74: 796-800.

Parshall, T. 1999. Documenting forest stand invasion: fossil stomata and pollen in forest hollows. Canadian Journal of Botany 77: 1529-1538.

Pisaric, M. F. J., J. M. Szeicz, T. Karst, and J. P. Smol, 2000. Comparison of pollen and conifer stomates as indicators of alpine treeline in northwestern Canadian lake sediments. Canadian Journal of Botany 78: 1180-1186.

Pisaric M. F. J., G. M. MacDonald, L. C. Cwynar, and A. A. Velichko, 2001. Modern pollen and conifer stomates from north-central Siberia lake sediments: their use in interpreting Late Quaternary fossil pollen assemblages. Arctic, Antarctic, and Alpine Research 33: 19-27.

Wick, L., and W. Tinner, 1997. Vegetation changes and timberline fluctuations in the Central Alps as indicators of Holocene climatic oscillations. Arctic and Alpine Research 29: 445-458.

Yansa, Catherine H., 1995. An Early Postglacial Record of Vegetation Change in southern Saskatchewan, Canada. M.Sc. thesis, Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan. See particularly Plates pp. 194-195.

Charlotte Sweeney has a picture of Picea stomata on her web page at http://www.kv.geo.uu.se/cas.html and hopes to have the key drafted by July this year (2001).

---

Notes: This item was posted to the QUATERNARY discussion list on May 10, 2001. It was printed, with permission, in CAP Newsletter 24(1): 15, 2001.