What are some of the worst weeds?
The environmental and management impacts of non-native plants can range from negligible to very serious based on a number of factors. The list below reflects a combination of criteria including; 1) invasive plants that currently have a major impact on the ecology, and 2) invasive plants that have the greatest potential to have a future impact if not controlled. Note: This list is not comprehensive, but a highlight of some of the most problematic weeds. The photo gallery offers a close look at these problem plants. Sweet fennel Scientific Name: Foeniculum vulgare Origin: Mediterranean region Fennel was introduced to park islands in the late 1800’s and was first spread by animals along roadsides. It invades areas where the soil has been disturbed, and prevents native species from becoming reestablished in these areas. It outcompetes native plants for water, light, nutrients and possibly through chemical toxicity. Fennel currently grows on San Miguel, Santa Rosa and Santa Cruz Islands. Bl
