Cultural Burning for Sourberry Basketry Material in Mariposa County, 2022-2023

Development of this research design attempted to help understand the effects of differing cultural cultivation techniques of sourberry shrubs (Rhus aromatica) for basketry material in Mariposa County. With the permission of Chairman Ron Goode, a randomized complete block design experiment was implemented in a old growth sourberry stand to assess quantitative measures of basketry production. Median plant height was assessed for each treatment area before any application of cultural management. Each 10m x 10m block contains four plots (4m x 4m) that have treatments randomly selected for each plot. Randomly selected treatments are one of the following: (1) Control, (2) Coppicing, (3) Coppicing + Burning, (4) Coppicing + Burning + Raking (or the subsequent mixing of ash back into the soil profile). Due to difficulty in implementation of treatments, block size was limited to 3 for this pilot study. Each treatment was implemented in the winter of 2022. Basketry material was harvested by community basket weavers in late summer/early fall of 2023, before the research team could evaluate basketry materials. The research team pivoted count data to assess the total number of quality basketry sticks harvested from each treatment. 6410 sourberry stems were counted in all of the blocks, and 177 stems were harvested.

本研究旨在阐明马里波萨县用于篮筐编织原料的酸果灌木（*Rhus aromatica*，俗称sourberry shrubs）不同栽培管理措施的效应。经罗恩·古德（Ron Goode）主席许可，研究团队在一片成熟酸果灌木林分内开展了完全随机区组设计（randomized complete block design）试验，以评估篮筐编织原料的量化生产指标。在实施各项栽培管理措施前，研究人员对各处理区域的植株株高中位数进行了测定。每个10米×10米的区组包含4个4米×4米的样地，各样地随机分配一种处理方式。随机选取的处理方式包括以下四类：(1) 对照组（Control），(2) 截干更新处理（Coppicing），(3) 截干更新+焚烧处理（Coppicing + Burning），(4) 截干更新+焚烧+耙耕（或后续将灰烬回拌至土壤剖面）处理（Coppicing + Burning + Raking）。由于处理实施存在一定难度，本预试验的区组数量限定为3个。所有处理均于2022年冬季实施。2023年夏末秋初，社区篮筐编织者在研究团队开展原料评估前，完成了篮筐编织原料的采收工作。研究团队对计数数据进行转换分析，以评估各处理组采收的优质编织枝条总数量。所有区组中共统计得到6410根酸果灌木枝条，最终采收枝条177根。