Some of these may be affiliate links, meaning we earn a small commission if items are purchased. Smooth Cordgrass is an interesting invasive plant that grows in salt marshes, bays, and creeks. A little more about me. The following 39 plants are the most invasive species in California as ranked by the California Invasive Plants Council.â They run a ton of tests and studies to come up with their list and I’ve included some of the details below. Distribution – how much of California land is affected by the invasive species. Simply put, they should not be planted. This means that sand can’t blow past patches of beachgrass to interior dunes, changing the landscape and ecology of the dunes. The ISCC asked the CISAC to create a list of “invasive species that have a reasonable likelihood of entering or have entered California for which an exclusion, detection, eradication, control or management action by the state might be taken" (CISAC Charter, Article IIIB). The eerily-named Creeping Water Primrose is another aquatic plant brought to the US for its ornamental value. Invasive plants tend to out-compete California’s native flora for resources such as space, light, water, and nutrients, are sometimes avoided by animals which can … Although Fennel is best known as a culinary and medicinal herb, there are varieties that aren’t used for culinary purposes that are considered a highly invasive plant in many areas of California. They’re also a fire hazard. While some species are native to California and may not be invasive, there is at least one species considered non-native and quite invasive. Invasiveness – how effectively does it take over the areas it invades? It’s found in deserts, the San Francisco Bay Area, and even in more remote areas like Shasta. It outperforms native plant species, starving them of the resources they need to survive. the invasive plants of greatest concern are: Annual Grasses Almost all of the grasses common in southern California today are non-native species from the Old World. Another weed with a beautiful flower, the Spotted Knapweed came to California in the late 1800’s, most likely via contaminated seed. Red Brome is mostly found in Southern California, although pockets of it show up throughout the rest of the state. Common Name: English Ivy And Algerian Ivy. While it’s native to South America, it has infested freshwater regions of California. The leaves are both under and above the water, causing the stems to get tangled and form mats. Invasive plants often increase the frequency of fires by providing more-continuous fuels that are easier to ignite. Many plants we consider for the list of invasive list meet some but not all of the invasive list criteria. Once they take hold in an area, they prevent other species’ seed from germinating due to their thin, dense strands. As its name implies, it originates from Northern Africa and the Middle East, but made its way to the Americas and quickly invaded many native regions of California. As an Amazon Associate, I earn from qualifying purchases. I created Epic Gardening to help teach 10,000,000 people how to grow anything, no matter where they live in the world. Medusahead was discovered in America in 1887 and likely came from contaminated seed from the Mediterranean area. Invasive Plants Invasive plants degrade habitat and water quality in Southern California. Many invaders have already established populations in various regions of California and occur in different stages of the invasion process. PlantRight partners with retail nurseries of all types and sizes to prevent the spread of invasive plants. Clicking on the scientific name will take you to the Plant Profile, where you’ll find links to more information on the plant. This tall grass has broad, bluish blades and grows into a large, handsome clump. Keep in mind, Sweet Anise is the preferred food of the Anise Swallowtail butterfly, noted in 1850âs by per Arthur Shapiro UC Davis field guide. On top of that, these thick mats will often become havens for mosquitoes. It thrives in shrublands and dunes and was originally brought to California for pasturing. It survives in freshwater, not saltwater, replacing native plants like cattails and other wetland plants. To make matters worse, its seeds are sticky and are spread by wildlife and humans. Native to South America (especially Brazil and Argentina), this aquatic weed invades freshwater areas of California. PlantRight 701 views. Its seeds can remain viable for up to 80 years! Growing Conditions: Grow in full sun to full shade. Common Name: Creeping Waterprimrose, Uruguay Waterprimrose. invasive species that are sold at garden centers, 5 Ways Youâre Feeding Your Garden Birds Wrong. Clicking on the scientific name will take you to the Plant Profile, where you’ll find links to more information on the plant. It’s sold in big box and garden stores because of its beautiful flowers, but tends to grow and reproduce at astonishing rates, leading to millions of dollars per year in plant management fees. Water hyacinth. We won't sell or give away your email address. The picture above is Tamarix Chinensis, but the true invasive species is Tamarix Ramosissima or Saltcedar. Bromus Tectorum Invasive alien plants are invading approximately 700,000 ha year −1 of natural communities in the United States (Pimentel et al., 2002).Invasive alien plants are defined as alien plants that reproduce offspring in very large numbers and at large distances from parent plants and thus have the potential to spread over a considerable area (Richardson et al., 2000). Thought to be native to eastern Asia, the Giant Reed was introduced to the US way back in the early 1800’s. It’s a tree / shrub that can end up being around 13 feet tall. ‘Canyon Prince’ is a popular selection that you can try in your Southern California garden. It has the nasty tendency to convert natural habitats to annual grasslands, especially coastal areas. Cattle can’t eat it to get rid of it either! ), ryegrasses (Lolium spp. California Invasive Plant Inventory Database. In fact, it’s the most serious rangeland weeds in the entire state of California. The French broom is another plant that looks beautiful, but ends up being invasive in every area it’s introduced except its native region, the Mediterranean. Description: Golden brown seaweed, growing up to nine feet. It’s been in California for over two decades, but is growing at an alarming rate, making it a growing concern for plant biologists and conservationists. Again, it is a mat-forming plant that has bright yellow-orange flowers. New content will be added above the current area of focus upon selection It will even survive fires, resprouting and taking advantage of newly-cleared area to propagate. Smallflower Tamarisk is a shrub that loves to invade the shores of lakes and streams. Common Name: Parrotfeather, Brazilian Watermilfoil, Parrotfeather Watermilfoil, Thread-Of-Life. This European and western Asian ivy shows up on the Californian coasts and outcompetes almost everything in Californian forests as well. The water hyacinth is known among botanists as one of the worst aquatic plants in the world. Common Name: Hydrilla, Water Thyme, Florida Elodea. As usual, it was introduced to California via the aquarium trade. Watercraft are the largest vectors for spreading aquatic invasive species (AIS), such as quagga and zebra mussels into new waterways, making boat inspections a vital aspect of protecting Lake Tahoe and other nearby water bodies. However, it reproduces only by seed and not vegetatively, unlike many of the nastier weeds on this list. ... self-seeding, it has spread to more than 25 states through Central and Eastern US, and can be found as far west as California. It will clump together and raise other plants out of the water. Impact – how large is the effect it has on the environment? Hi, I'm Kevin. This prevents water in the marshes from flowing inward, meaning that more sediment accumulates. Common Name: Purple Veldtgrass; African Veldtgrass; Perennial Veldt Grass. It’s unique in that it can harm livestock when it lodges in their mouths and eyes. Home Â» The 39 Most Invasive Plant Species in California. Dense-flowered cordgrass is similar to Smooth Cordgrass, also growing in the salt marshes of California. It was initially brought in for erosion control, but ended up crowding out plants native to California and even increases the frequencies of fires (as if we need more of that). Common Name: Scarlet Wisteria; Red Sesbania; Rattlebox; Chinese Wisteria. On the plus side, almost all Parrotfeather plants are female, so it doesn’t produce seeds. If you’re a gardener in California (or other states in the Pacific Northwest), chances are good you’ve had to battle one of these 39 invasive species. It’s drought resistant, making it perform well in California’s current water crisis. Common Name: Creeping Waterprimrose; California Waterprimrose. Each has its own wildlife niche, whether it’s birds, butterflies, hummingbirds, native bees or the plethora of pollinators. In 2011 in Ventura County, while searching for the non-native and invasive brown widow spider, Latrodectus geometricus, a discovery was made of a large brown spider that was not recognized as being part of the southern California spider fauna. This article contains incorrect information, This article is missing information that I need. Scientific Name Common Name Type Subtype Extent Risk of Introduction First Source; Abgrallaspis aguacatae: armored scale : arthropod : scale, aphid Common Name: Cape-Ivy; German Ivy; Italian Ivy; Ivy Groundsel; Parlor Ivy; Water Ivy. Incredible Way the CIA Stole a Soviet Submarine During Cold War - Duration: 14:12. Site by, Chrysanthemoides monilifera ssp. The Spanish Broom is a close relative to the Scotch Broom, which we covered already. Common Name: French Broom; Soft Broom; Canary Broom; Montepellier Broom. 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