Bachelor of Science (B.S.)
Science & Environmental Policy
Invasive species in the United States cost the federal and state governments billions of dollars per year and are spreading through wildlife habitat at a rate of about 700,000 acres per year. Information on effective methods of controlling various invasive species is crucial to land managers and others who seek to remove invasive, exotic species and restore their lands to a more natural state. This study examines which of three methods will work most effectively at controlling fennel (Foeniculum vulgare) in a small-scale infestation in two sites in Salinas, while costing the least. The methods are: digging out individual plants with a shovel, chopping the plants repeatedly during the summer with a machete, or chopping the plants and immediately spraying the stumps with an application of the herbicide Rodeo. I discovered that the most effective method was digging each plant individually, with chopping and spraying with herbicide a close second. The method of chopping repeatedly was not effective at all, with a mortality rate very similar to my control group of plants which received no treatment. I also found that the least expensive method was chopping and spraying, with chopping repeatedly a close second. Digging the individual plants was the most time consuming and therefore the most expensive. My recommendation for controlling fennel based upon my results is that if herbicide application is not an issue, then chopping and spraying each plant with an herbicide is the best treatment method. If soils are soft and the infestation is small, digging up each individual plant is the best treatment method.
Gwinn, Abigail, "The cost and effectiveness of small-scale control methods on fennel, Foeniculum vulgare, in Natividad Creek Park, Salinas, CA" (2007). Capstone Projects and Theses. 50.