Dittrichia graveolens (stinkwort) is a fall-flowering, sticky aromatic annual (family Asteraceae) that is native to southern Europe, northern Africa, and southwestern Asia.  It was first recorded in California in 1984 and has rapidly spread across many parts of the state since its introduction. Stinkwort has glandular-haired leaves and stems and grows to a height of […]

Dipsacus sativus (Fuller’s teasel) is a biennial (family Dipsacaceae) found in California’s Coastal and Peninsular Ranges and the San Francisco Bay area. It favors disturbed sites, including grasslands, roadsides, ditches and riparian sites. Fuller’s teasel’s spiny flower heads were used for carding wool before metal carding combs were created. Teasel plants may grow to form […]

Dipsacus fullonum (wild teasel) is a biennial forb/herb (family Dipsacaceae) that is native to Eurasia and northern Africa and naturalized across much of the United States and Canada. It can grow up to 2.5 m and is characterized by its prickly stems, leaves, and inflorescences, lanceolate leaves that are typically fused in pairs around the […]

Digitalis purpurea (foxglove) is an erect, knee-high to head-high herbaceous perennial (family Scrophulariaceae) found along the central and northern California coast and in Sierra Nevada foothills, infesting moist meadows and roadsides. All parts of the plant are toxic. It readily colonizes areas of soil disturbance, forming dense patches that displace natural vegetation.

Descurainia sophia (flixweed) is an annual or biennial (family Brassicaceae) found throughout California along roadsides, in agricultural fields, disturbed desert areas, scrub, grasslands and woodlands. It is most common in the northeastern region, particularly in the Great Basin. It tends to prefer well-drained sandy or stony soils. Flowering flixweed plants can be toxic to cattle […]

Delairea odorata (=Senecio mikaniodes) (Cape-ivy, German-ivy) is a perennial vine (family Asteraceae) found along the coast of California and in the San Gabriel Mountains. Cape-ivy is especially problematic in coastal riparian areas, though it may also invade inland riparian areas, moist forests, and oak woodlands. Vines are known to form dense mats of vegetation over […]

Rytidosperma penicillatum (= Danthonia pilosa) (hairy wallaby grass) is a perennial (family Poaceae) native to Australia. It is also found in Oregon and is expanding in disturbed open areas, meadows, and conifer forests of northern California (more recently also in southern CA). Plants grow to less 1 m high, grow as small bunch grasses, and have […]

Egeria densa (Brazilian Egeria) is a common aquatic perennial (family Hydrocharitaceae) that occurs in lakes, springs, ponds, and streams. Its underwater growth significantly retards water flow and decreases the abundance and diversity of native plant seeds in lake bottoms. It was introduced as a freshwater aquarium plant.

Lepidium draba (hoary cress) is a perennial herb (family Brassicaceae) found most commonly in riparian areas and marshes of the central coast of California. It is also found in the southwestern region of the state, the Sacramento Valley, and the Klamath Range, where it is very invasive. This plant quickly colonizes disturbed sites, irrigated agricultural […]

Cakile maritima (European sea rocket) is a succulent annual or perennial (family Brassicaceae) found in coastal dunes spread throughout the coast of California. European sea rocket is a common invasive plant, but its impacts appear to be relatively minor. European sea rocket reproduces by seed, which is distributed by ship ballasts, sand transport, tidal movement, […]