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