Rhododendron is a very large genus of about 1,024 species of woody plants in the heath family (Ericaceae). They can be either evergreen or deciduous. Most species are native to eastern Asia and the Himalayan region, but smaller numbers occur elsewhere in Asia, and in North America, Europe and Australia. It is the national flower of Nepal, the state flower of Washington and West Virginia in the United States, the state flower of Nagaland in India, the provincial flower of Jiangxi in China and the state tree of Sikkim and Uttarakhand in India. Most species have brightly colored flowers which bloom from late winter through to early summer.
Azaleas are flowering shrubs in the genus Rhododendron, particularly the former sections Tsutsusi (evergreen) and Pentanthera (deciduous). Azaleas bloom in the spring, their flowers often lasting several weeks. Shade tolerant, they prefer living near or under trees. They are part of the family Ericaceae.
Rhododendron canadense, the rhodora or Canada rosebay, is a deciduous flowering shrub that is native to northeastern North America.
Rhododendron occidentale, the western azalea or California azalea, is one of two deciduous Rhododendron species native to western North America. The western azalea is known to occur as far north as Lincoln and Douglas Counties in Oregon and as far south as the mountains of San Diego county. Typically found in the coastal ranges of western North America, it also grows in the Cascade and Sierra Nevada mountain ranges, but is not known east of them.
Rhododendron maximum — its common names include great laurel, great rhododendron, rosebay rhododendron, American rhododendron and big rhododendron — is a species of Rhododendron native to the Appalachians of eastern North America, from Alabama north to coastal Nova Scotia.
Rhododendron calendulaceum, the flame azalea, is a species of Rhododendron native to North America. All parts of this plant are poisonous to humans.
Rhododendron macrophyllum, the Pacific rhododendron, California rosebay, California rhododendron, coast rhododendron or big leaf rhododendron, is a large-leaved species of Rhododendron native to the Pacific Coast of North America. It is the state flower of Washington.
Rhododendron viscosum, the swamp azalea, clammy azalea or swamp honeysuckle, is a species of flowering plant in the heath family Ericaceae. This deciduous shrub, growing to 2.5 m (8.2 ft) tall and broad, is native to the eastern United States. It has rounded matt green leaves. In early summer it produces funnel-shaped white flowers flushed pink. The flowers have prominent stamens and are strongly fragrant.
Trillium vaseyi, the sweet wakerobin or sweet beth, is a spring flowering perennial plant which is found only in the southeastern United States, primarily in the southern part of the Appalachian Mountains but with a few populations farther south.
George Vasey was an English-born American botanist who collected a lot in Illinois before integrating the United States Department of Agriculture (USDA), where he became Chief Botanist and curator of the greatly expanded National Herbarium.
Cirsium hydrophilum is a species of thistle which is endemic to California, where it is found only in the San Francisco Bay Area and the Sacramento-San Joaquin River Delta. This native thistle grows in wet boggy habitats.
Salvia vaseyi, the scallop-leaf sage, bristle sage or wand sage, is a perennial native to the western Colorado Desert. Flowers grow in compact clusters on 1 to 2 ft spikes. The .5 inches (1.3 cm) flowers are white, with whitish bracts, calyx, and leaves, blooming from April to June. The specific epithet was named after botanist George Vasey or for his son, George Richard Vasey, who collected the type specimen.
Rhododendron periclymenoides, the pink azalea or pinxter flower, is a species of shrub in the heath family Ericaceae. It is native to eastern North America, where it is widespread from Alabama to New Hampshire. It is often found in riparian areas, in wet to dry forests.
Rhododendron prunifolium, the plumleaf azalea, is a wild azalea that grows only in a few counties along the Georgia–Alabama border in the Chattahoochee River Valley. It is considered the rarest azalea in the Eastern United States. Providence Canyon is one of the most popular places to view the plumleaf azalea in the wild.
Rhododendron arborescens, also known as smooth azalea or sweet azalea, is a species of flowering plant in the family Ericaceae, native to the eastern seaboard of the United States.
Rhododendron austrinum is a species of flowering plant in the heath family known by the common names Florida flame azalea, honeysuckle azalea, Southern yellow azalea, and orange azalea. It is native to the southern United States, where it can be found in Alabama, Florida, Georgia, and Mississippi. It is also a common ornamental plant.
Rhododendron prinophyllum, the early azalea, is a rhododendron species native to the eastern and southern United States. It is a deciduous shrub that grows 4 to 8 feet in height. Flowers are pink.
Pieris floribunda is a North American species of broadleaf evergreen shrub, a member of the fetterbush genus in the blueberry family (Ericaceae). It is commonly known in North America as mountain fetterbush or mountain andromeda. All parts of Pieris floribunda are poisonous if ingested. In landscapes it should be grown in full to part shade, out of windy locations, and have a good quality soil with much organic matter with acidity of pH 4.5 to 6.5.
North American azaleas are flowering shrubs in the genus Rhododendron, section Pentanthera, subsection Pentanthera, so named because they all have five stamens. Most are in the United States, with one species found in Canada and one being found in Mexico. North American azaleas are commonly confused with azaleas of Asian origin, the evergreen azaleas. North American azaleas are deciduous and produce two types of buds. One is a larger and produces about 20 flowers while the other bud produces a leafy shoot. The flower color, fragrance, and number of stamens vary among species.
Potamogeton vaseyi, common name Vasey's pondweed, is a species of plant found in North America. It is listed as an endangered species in Indiana, Massachusetts, and Pennsylvania, and is listed as threatened in Connecticut, Maine, Michigan, and New Hampshire, and as presumed extirpated in Ohio.
