RENTZ, ERIN D.* and ROBERT W. PATTERSON. Department of Biology, San Francisco State University, 1600 Holloway Ave., San Francisco, CA 94132. - Effects of burning on the anatomical structure of Corylus cornuta and Xerophyllum tenax, plants commonly used in California aboriginal basketry.
For centuries, Native Americans in northwestern California have
utilized fire as a tool to manage important plant resources. Regular
burning is performed to clear excess brush and increase the quality
and quantity of plant species used by tribes in this region as a food
source or to weave baskets. Xerophyllum tenax (bear grass) and
Corylus cornuta (hazelnut) are two plant species which require
regular burning to produce materials suitable for basket weaving.
Leaves and stems produced after fire are straighter, more flexible and
more even from base to tip than those produced on unburned plants. The
goal of this project was to determine how fire affects anatomical
structure of Xerophyllum tenax and Corylus cornuta and
to determine the structural characteristics important to weaving. We
collected leaf and stem samples from plants in unburned populations as
well as from burned populations, one year after a fire and used light
microscopy to compare anatomical structure. In Xerophyllum
tenax, post-fire leaf growth exhibited a reduction of support
fibers along the adaxial and abaxial surfaces as well as a reduction
in secondary wall thickness in fibers. This is consistent with
morphological characteristics weavers recognize as good quality.
Key words: anatomy, basketry, Corylus, fire, Xerophyllum