Skip to main content
profile image
Selected Works of Vânia Coelho
Article
Germination of Invasive Plant Seeds after Digestion by Horses in California
Natural Areas Journal (2008)
  • Laura D. Quinn, Department of Natural Sciences, and Mathematics, Dominican University of California
  • Mietek Kolipinski, Department of Natural Sciences, and Mathematics, Dominican University of California
  • Vânia R. Coelho, Department of Natural Sciences and Mathematics, Dominican University of California
  • Bonnie Davis, Department of Natural Sciences, and Mathematics, Dominican University of California
  • John-Mary Vianney, Department of Natural Sciences, and Mathematics, Dominican University of California
  • Orgiltuya Batjargal, Department of Natural Sciences, and Mathematics, Dominican University of California
  • Monika Alas, Department of Natural Sciences, and Mathematics, Dominican University of California
  • Sibdas Ghosh, Department of Natural Sciences, and Mathematics, Dominican University of California
Abstract
Using a unique sterile design intended to eliminate outside seed contamination of horse feces, we investigated whether weed seeds germinate after digestion by horses. Feces were collected from selected National Parks and other locations in central and northern California. All potted fecal samples were irrigated and grown in an enclosed sterile nursery environment. Thirty-two plant species emerged from these fecal samples, 24 of which were not native to California. None of these were identified on the California Department of Agriculture's Noxious Weed List, which is used as a basis to certify equine feed as weed free. However, seven of the non-native species are identified as moderately invasive on the California Invasive Plant Council's (Cal-IPC) list. These species are: Hirschfeldia incana, Hordeum marinum, Lolium multiflorum, Mentha pulegium,Rumex acetosella, Trifolium hirtum, and Vulpia myuros. In addition, the following four non-native plants are listed at the limited invasiveness level on the Cal-IPC list: Hypochaeris glabra, Lythrum hyssopifolium, Medicago polymorpha, and Poa pratensis. Because we did not survey invasive plant cover in locations from which we sampled, we cannot guarantee that species identified in our samples would have also germinated in the field. Our results add to a growing body of literature documenting germination of seeds after passing through the digestive system of horses and suggest that conscientious horse owners should select feed sources that are free of weeds. We also find that the current list of noxious weeds used to certify weed-free feed for equines should be comprehensive.
Keywords
  • California,
  • horse feces,
  • horse manure,
  • invasive plant germination,
  • non-native plants,
  • weed seeds
Disciplines
Publication Date
October, 2008
DOI
10.3375/0885-8608(2008)28[356:GOIPSA]2.0.CO;2
Citation Information
Laura D. Quinn, Mietek Kolipinski, Vânia R. Coelho, Bonnie Davis, et al.. "Germination of Invasive Plant Seeds after Digestion by Horses in California" Natural Areas Journal Vol. 28 Iss. 4 (2008) p. 356 - 362 ISSN: 0885-8608
Available at: http://works.bepress.com/vania-coelho/2/