Cal-IPC Projects
2023 Cal-IPC Symposium, Oct. 25-28
Connect with colleagues at the 2023 Cal-IPC Symposium, Oct. 25-28, at Chico or Online. Join session talks, discussion groups, and posters covering a wide range of topics related to invasive plant biology and management. Chat with sponsors/exhibitors, engage during discussion groups, talk to poster presenters, and meet with friends and colleagues....Read MoreDesert Knapweed Containment
Volutaria tubuliflora, or desert knapweed, is a plant from north Africa that has recently been found in California. These are the only known sites in North America. There are two small sites on the coast in San Diego County and Orange County, and a major infestation in Borrego Springs, 50 miles inland in the Sonoran Desert. This infestation has spread over 15 square miles, and range modeling shows that desert knapweed would find suitable conditions across the American Southwest. In the 2016 superbloom, partners mapped and removed populations across the area during the January to April...Read MoreProtecting Sierra Tree Mortality Zones
Cal-IPC, in cooperation with the California Dept. of Food and Agriculture and county Agricultural Commissioners in the Central Sierra, is working to control invasive plants that threaten to spread into areas with extensive tree mortality. Drought conditions have enabled native bark beetles to kill millions of trees in the region, making it more important than ever to control invasive plant populations which can spread into disturbed areas (more information on tree mortality in the Sierra). To support prio...Read MoreSouth Central Coast Eradication
This project targets five invasive plant species for region-wide eradication in the South Central Coast region (San Luis Obispo and Santa Barbara counties): Canada thistle, Russian wheatgrass, Japanese dodder, Dalmation toadflax and European sea lavender. Eradication is the gold standard of invasive plant control because it means the threat from that species has been eliminated (unless the species is re-introduced to the region). It is more effective and more cost-effective than long-term ongoing containment. The species in this effort were prioritized through a comprehensive assessment with r...Read MoreArundo Mapping
Arundo donax, or giant reed, is one of the most damaging invasive plants in California. Its dense canes crowd riparian areas, destroying wildlife habitat and consuming extra water. Major removal projects have been undertaken in many coastal watersheds, including the Santa Ana River in southern California, and the Salinas River on the central coast. In 2008-2010, Cal-IPC undertook mapping Arundo in coastal watersheds from Mexico to Monterey to support removal efforts. As part of Proposition 1 funding to...Read MoreSF Bay Sea Lavender Control
Cal-IPC and partners prioritized Algerian sea lavender (Limonium ramosissimum) and European sea lavender (L. durisculum) as top priorities for removal to protect San Francisco Bay tidal marshes. These plants are found in several other locations along the California coast (for instance, Morro Bay, Carpenteria Marsh near Santa Barbara, and San Diego), and are a prime candidate for early eradication before they spread further. California's salt marsh habitat is home to a unique assemblage of plants and wildlife, and much of this habitat has been lost to development. Few weed spe...Read MoreNorthcoast Knotweed Eradication
Invasive giant knotweeds routinely make the list of the worst invasive species in the world. They have wreaked havoc in western Oregon and Washington, taking over riparian areas. There are only a handful of infested areas in California, and the main challenge is on the north coast, in Humboldt and Del Norte counties. Multiple species of knotweed, including Japanese knotweed (Fallopia japonica), giant knotweed (F. sachalinensis) and Himalayan knotweed (Periscaria wallichii) are found in the region, at about 100 sites in all. Knotweeds are notoriously difficult to get...Read MoreSierra Nevada Meadows Protection
Sierra Nevada meadows are valued for their ecosystem functions, regulating water storage and flow, and providing important wildlife habitat. Invasive plants can significantly alter vegetation communities, degrade wildlife habitat, and potentially reduce water storage and carbon sequestration functions. Our project improves understanding of these impacts and strengthens capacity to effectively address the threat. The primary activity of this project is characterizing the level of threat in Sierra meadows from invasive plants through development of a “Read MoreInvasive Spartina Eradication
Pacific cordgrass (Spartina foliosa) is a major component of tidal marsh vegetation in San Francisco Bay, which historically covered thousands of acres across the region. In the 1970s, the Army Corps of Engineers introduced Atlantic cordgrass (Spartina alterniflora) to the Bay, which hybridized with its native cousin. The hybrids expanded aggressively across lower tidal mudflats and tidal ...Read More