Are Willow and Semele both species of tree?
no
Willow
Willows, also called sallows, and osiers, form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere.
 Most species are known as willow, but some narrow-leaved shrub species are called osier, and some broader-leaved species are referred to as sallow (from Old English "sealh", related to the Latin word "salix", willow).
 Some willows (particularly arctic and alpine species) are low-growing or creeping shrubs; for example, the dwarf willow ("Salix herbacea") rarely exceeds 6 cm in height, though it spreads widely across the ground.
Semele
Semele ( ; Greek: Σεμέλη "Semelē"), in Greek mythology, daughter of the Boeotian hero Cadmus and Harmonia, was the mortal mother of Dionysus by Zeus in one of his many origin myths.
Salix humboldtiana
Salix humboldtiana, the Humboldt's willow, is a tree species of willow native to North and South America, growing along watercourses. Salix acutifolia
Salix acutifolia, also known as Siberian violet-willow, long-leaved violet willow or sharp-leaf willow, is a species of flowering plant in the Salicaceae family, native to Russia and eastern Asia.
 It is a spreading, deciduous shrub or tree, growing to 10 m tall by 12 m wide.
 The young shoots are deep purple with a white bloom.
 The leaves are narrow, up to 10 cm long.
 The catkins are produced in early spring, before the leaves.
 Older bark has a fine, netted pattern. Salix caroliniana
Salix caroliniana, commonly known as the coastal plain willow, is a shrub or small tree native to the southeastern United States, Mexico and parts of Central America and the Caribbean.
 It is an obligate wetland species and grows as an emergent species in the Everglades.
 In the absence of fire, "S. caroliniana" can convert herbaceous wetlands to forested wetlands.
 Although fires kill large woody stems and the species does not reproduce by rhizomes or root sprouts, it sprouts readily after fire.
 As a result, the total number of stems does not change, but fire converts "S. caroliniana" from a tree into a shrub. Salix myrsinifolia
Salix myrsinifolia, known as the dark-leaved willow or myrsine-leaved willow, is a species of willow native to Europe and Western Siberia.
 It forms a 2 - high shrub.
 In the north it becomes often a tree up to 8 m tall. Carrierea calycina
Carrierea calycina is a species of tree in the willow family.
 It is native to China.
 Common names include goat horn tree in English and yang jiao shu in Mandarin. Salix bonplandiana
Salix bonplandiana (Bonpland willow), (Span.: "ahuejote", "sauce", "ahujote", and "huejote"), is a perennial species of willow tree native to southern and southwest Mexico and extending into central Guatemala; in western Mexico it is a tree of the Sierra Madre Occidental cordillera, but also occurring in other small locales, for example Baja California Sur, northern Sonora, San Luis Potosi, etc.
 A core disjunct area occurs in central and southeast Arizona, in advantageous locales, especially associated with higher elevations and water. Salix atrocinerea
Salix atrocinerea, commonly called grey willow or large gray willow, is a species of willow.
 It is a bush or small tree up to 12 m tall.
 As a pioneer species of willow, it quickly colonizes poor soils. Salix sepulcralis group
The "Salix sepulcralis" group is a cultivar group containing all cultivars of hybrids between "Salix alba" and "Salix babylonica".
 The "sepulcralis" or × "sepulcralis" trees are sometimes referred to as white weeping willow or glaucous weeping willow in reference to the mixed appearance from the parent species.
 It was first described by L. Simonkai in 1890 from trees growing in Romania.
 The group contains both weeping and nonweeping cultivars, though the best-known of its cultivars is 'Chrysocoma', the most widely grown weeping tree.
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