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Providing evidence to improve practice

Individual study: Managing Medusahead (Taeniatherum caput-medusae) on Rangeland: A Meta-Analysis of Control Effects and Assessment of Stakeholder Needs

Published source details

James J.J., Gornish E.S., DiTomaso J.M., Davy J., Doran M.P., Becchetti T., Lile D., Brownsey P. & Laca E.A. (2015) Managing Medusahead (Taeniatherum caput-medusae) on Rangeland: A Meta-Analysis of Control Effects and Assessment of Stakeholder Needs. Rangeland Ecology & Management, 68, 215-223


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Other biodiversity: Use grazers to manage vegetation Mediterranean Farmland

A meta-analysis from 2015 of four studies from annual rangelands in California, USA, found that grazing decreased the abundance of medusahead Taeniatherum caput-medusae. Plants: The abundance of medusahead was lower in plots that were grazed, compared to ungrazed, one year after grazing (reported as the response ratio of grazed to ungrazed plots: –0.7 log response ratio), but not 2–4 years after grazing. Methods: The Web of Knowledge, Agricola, and Digital Dissertations databases (and others managed by the University of California) were searched for publications from 1960 to 2013 (keywords not reported). Five studies from 1969 to 2011 were meta-analysed. There were four studies from California (response ratios from –2.4 to 0.4) and one study from Oregon (response ratios from 0.17 to 0.48: all positive, and so grazing decreased the abundance of medusahead only in California). Sheep or cattle were used for grazing, for 5–180 days, with an average stocking rate of 5.6 animal unit months (AUMs). The average plot size was 0.21 ha.