Plants & Trees Encyclopedia

Yucca — The yuccas comprise the genus Yucca of 40-50 species of perennials, shrubs, and trees in the agave family Agavaceae, notable for their rosettes of evergreen, tough, sword-shaped leaves and large terminal clusters of white or whitish flowers. They are native to the hot and dry parts of North America, Central America, and the West Indies. Yuccas have a …

Yew — Yew is the common name for the 8 species of the genus Taxus in the yew family, Taxaceae. These shrubs or small trees have thin, reddish-brown to purple, scaly bark. Native to the temperate regions of the Northern Hemisphere, yews generally grow well in moist soils and shade, with some species growing to heights of 23 m (75 …

Yellowwood — Cladrastis (Yellowwood) is a genus of seven species of flowering plants in the family Fabaceae, six native to eastern Asia, and one to southeastern North America. They are small to medium-sized deciduous trees typically growing 10–20 m tall, exceptionally to 27 m tall. The leaves are compound pinnate, with 5–17 alternately arranged leaflets. The flowers are fragrant, white …

Yam — Yam is the common name for some species in the genus Dioscorea (family Dioscoreaceae). These are perennial herbaceous vines cultivated for the consumption of their starchy tubers in Africa, Asia, Latin America and Oceania. There are hundreds of cultivars among the cultivated species. Yams are not sweet potatoes, but are used in a fashion similar to both sweet potatoes …

Witch Hazel — Witch-hazel (Hamamelis) is a genus of four species of flowering plants in the family Hamamelidaceae, with two species in North America (H. virginiana and H. vernalis), and one each in Japan (H. japonica) and China (H. mollis). They are deciduous shrubs or (rarely) small trees growing to 3-8 m tall, rarely to 12 m tall. The leaves …

Wisteria — Wisteria is a genus of about ten species of woody climbing vines native to the eastern United States and the East Asian states of China, Korea, and Japan. Aquarists refer to the species Hygrophila difformis, in the genus Hygrophila, as Water Wisteria. Wisteria vines climb by twining their stems either clockwise or counter-clockwise round any available support. They …

Wintergreen — Wintergreen is a group of plants. Wintergreen once commonly referred to plants that continue photosynthesis (remain green) throughout the winter. The term evergreen is now more commonly used for this characteristic. Some species of the shrub genus Gaultheria in the closely related family Ericaceae also demonstrate this characteristic and are called wintergreens in North America, the most common …

Willow, Babylon Weeping — Salix babylonica (Peking Willow or Babylon Willow) is a species of willow native to dry areas of northern China, but cultivated for millennia elsewhere in Asia, being traded along the silk road to southwest Asia and Europe. It is a medium-sized to large deciduous tree, growing up to 20-25 m tall. It grows rapidly, but has …

Willow, American Pussy — Salix discolor (American Pussy Willow) is a species of willow native to North America, one of two species commonly called Pussy Willow. It is native to the northern forests and wetlands of Canada (British Columbia east to Newfoundland) and the northeastern contiguous United States (Idaho south to Wyoming, and east to Maine and Maryland). It is …

Wheat — Wheat (Triticum spp.) is a domesticated grass from the Levant that is cultivated worldwide. Globally, wheat is an important human food, its production being second only to maize among the cereal crops; rice ranks third. Wheat grain is a staple food used to make flour for leavened, flat and steamed breads; cookies, cakes, pasta, noodles and couscous; and …