Trillium is a genus of about fifty flowering plant species in the family Melanthiaceae. Trillium species are native to temperate regions of North America and Asia, with the greatest diversity of species found in the southern Appalachian Mountains in the southeastern United States.
Trillium chloropetalum, also known as giant trillium, giant wakerobin, or common trillium, is a species of flowering plant in the family Melanthiaceae. It is endemic to the western U.S. state of California, being especially frequent in and around the San Francisco Bay Area.
Pseudotrillium is a monotypic genus of flowering plant in the family Melanthiaceae. Its sole species, Pseudotrillium rivale, is commonly known as the brook wakerobin. It is endemic to the Siskiyou Mountains of southern Oregon and northern California. The Latin specific epithet rivale means “growing by streams”, with reference to a preferred habitat.
Trillium ovatum, the Pacific trillium, also known as the western wakerobin, western white trillium, or western trillium, is a species of flowering plant in the family Melanthiaceae. It is found in western North America, from southern British Columbia and the tip of southwestern Alberta to central California, east to Idaho and western Montana. There is an isolated population in northern Colorado and southern Wyoming.
Trillium luteum, the yellow trillium or yellow wakerobin, is a species of flowering plant in the bunchflower family Melanthiaceae with native populations in the Great Smoky Mountains of the United States and surrounding areas.
Trillium discolor, the mottled wakerobin, pale yellow trillium, or small yellow toadshade, is a species of flowering plant in the family Melanthiaceae. It is native to areas of the Savannah River drainage system of Georgia, North Carolina and South Carolina such as Steven's Creek Heritage Preserve and Lake Keowee. It is found along moist stream banks in upland woods, on acidic to basic soils.
Trillium undulatum, commonly called painted trillium, painted lady, or trille ondulé in French, is a species of flowering plant in the bunchflower family Melanthiaceae. It is also known as smiling wake robin or striped wake-robin. The specific epithet undulatum means "wavy", which refers to the wavy edges of the flower petals. The plant is found from Ontario in the north to northern Georgia in the south and from Michigan in the west to Nova Scotia in the east.
Trillium cuneatum, the little sweet betsy, also known as whip-poor-will flower, large toadshade, purple toadshade, and bloody butcher, is a species of flowering plant in the family Melanthiaceae. It is native to the southeastern United States but is especially common in a region that extends from southern Kentucky through central Tennessee to northern Alabama. In its native habitat, this perennial plant flowers from early March to late April. It is the largest of the eastern sessile-flowered trilliums.
Trillium sessile is a species of flowering plant in the bunchflower family Melanthiaceae. The specific epithet sessile means "attached without a distinct stalk", an apparent reference to its stalkless flower. It is commonly known as toadshade or toad trillium. It is also called sessile trillium or sessile-flowered wake-robin,, however it is not the only member of the genus with a sessile flower.
Trillium stamineum, the twisted trillium, also known as the Blue Ridge wakerobin, is a species of flowering plant in the family Melanthiaceae. It is native to the southeastern United States, in Alabama, Mississippi and Tennessee. Its natural habitat is calcareous woodlands.
Trillium sulcatum is a species of flowering plant in the bunchflower family Melanthiaceae. The specific name sulcatum means "furrowed, grooved, or sulcate", which describes the tips of the sepals. It is most abundant on the Cumberland Plateau in central Tennessee and eastern Kentucky where it blooms in April and May. The species is commonly known as the southern red trillium or furrowed wakerobin.
Trillium decumbens, also known as the decumbent trillium or trailing wakerobin, is a species of flowering plant in the bunchflower family (Melanthiaceae). It is native to the southeastern United States, specifically Tennessee, Georgia, and Alabama, where it grows in mature deciduous woodlands or on open rocky wooded slopes.
Trillium albidum is a species of flowering plant in the bunchflower family Melanthiaceae. It is the only trillium characterized by a stalkless white flower. The species is endemic to the western United States, ranging from central California through Oregon to southwestern Washington. In the San Francisco Bay Area, it is often confused with a white-flowered form of Trillium chloropetalum. In northern Oregon and southwestern Washington, it has a smaller, less conspicuous flower.
Trillium reliquum, the relict trillium, Confederate wakerobin, or Confederate trillium, is a monocotyledon species of the genus Trillium, a perennial, flowering, herbaceous plant of the family Liliaceae. It is found only in the southeastern region of the United States: southwest, central and east central Alabama, Georgia, South Carolina and Tennessee. As a relict species, there are a few remaining groups but it was once more abundant when conditions were different. Significant habitat loss has occurred through clearing of forests for agricultural and pine farm uses.
Trillium petiolatum, the Idaho trillium, also known as the long-petioled trillium or round-leaved trillium, is a species of flowering plant in the family Melanthiaceae. It is native to the northwestern United States, in Idaho, Oregon, and Washington. The type specimen for this species was gathered by Meriwether Lewis in 1806 along the Clearwater River during the return trip of the Lewis and Clark Expedition.
Trillium angustipetalum, with the common name is narrowpetal wakerobin, is a species of Trillium, plants which may be included within the Liliaceae or the newer family Melanthiaceae.
Trillium kurabayashii is a species of flowering plant in the bunchflower family Melanthiaceae. The species is endemic to the western United States, occurring in extreme southwestern Oregon, northwestern California, and the Sierra Nevada of northern California. It was first described by John Daniel Freeman in 1975. The specific epithet kurabayashii honors Masataka Kurabayashi, a Japanese cytologist and population geneticist who first postulated the taxon’s existence. It is commonly known as the giant purple wakerobin, a reference to its conspicuously large, dark purple-red flower, one of the largest of any sessile-flowered trillium.
Trillium maculatum, the spotted wakerobin or spotted trillium, is a species of flowering plant in the family Melanthiaceae. It is found only in the eastern United States.
Trillium underwoodii, the longbract wakerobin, is a plant species found only in the southeastern United States.
Trillium viride, commonly called the wood wakerobin, is a species of flowering plant in the family Melanthiaceae. It is found in the central United States, in certain parts of Missouri and Illinois. The specific epithet viride means "youthful" or "fresh-green", an apparent reference to the color of the plant's flower petals. For this reason, it is also called the green trillium, not to be confused with other green-flowered trilliums such as T. viridescens and the green form of T. sessile, both of which are found in Missouri.
