ibclogo XVI International Botanical Congess


Abstract Number: 4166
Poster No. = 876


COMPARATIVE WOOD ANATOMY OF THE LAKE ATHABASCA SAND DUNE ENDEMIC WILLOWS (SALICACEAE)


Ranessa L. Cooper & David D. Cass, University of Alberta, Edmonton, Alberta, Canada


The Athabasca sand dunes are located on the south shore of Lake Athabasca in northern Alberta and Saskatchewan, Canada. Ten plant taxa are endemic to the Athabasca sand dunes, and four of these are willows (Salicaceae). These endemic willows (Salix brachycarpa Nutt. var. psammophila Raup, S. planifolia Pursh ssp. tyrrellii (Raup) Argus, S. silicicola Raup, and S. turnorii Raup) persist in desert-like conditions on large expanses of open sand. We have examined the wood anatomy of each endemic in comparison with that that of the associated boreal or arctic progenitor. Preliminary results indicate vessel element clustering in the endemics that may allow for more efficient water transport. The endemics and their progenitors may differ in pore distributions. Endemic willows have a higher proportion of wood fibers and distinct bundles of soft bast fibers which may provide extra support in the windy, open sand habitat.


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