Hamamelidaceae, the witch hazel family (order Saxifragales), comprising about 30 genera and about 100 species of shrubs and trees native to both tropical and warm temperate regions. Several species are cultivated as ornamentals.
Members of the family are characterized by alternate simple leaves and flowers usually having four or five often strap-shaped or small petals and four or five sepals. Sometimes either or both sepals and petals are lacking. Fruits are woody.
Both witch hazel (Hamamelis) and winter hazel (Corylopsis) are grown in temperate climates as ornamentals for their flowers that appear in very early spring. Various species of Fothergilla, sometimes known as witch alders, are also grown for their spring flowers as well as for their striking fall foliage.
Autumn leaf colour, changing from golden yellow to orange and scarlet, is also an outstanding trait of Persian ironwood (Parrotia persica), a small tree from northern Iran. Its flowers, produced before the leaves, have drooping stamens, lack petals, and have brown leaflike bracts. This tree’s close-grained wood is very strong, as are the twigs of the related Parrotiopsis jacquemontiana, which is used in its native Himalayan area for making baskets and bridges. A deciduous tree with petalless flowers, white bracts, and erect stamens, it is taller than Persian ironwood, reaching about 6 metres (20 feet). The still taller Japanese shrubDisanthus cercidifolius has dark purple flowers and leaves that turn crimson red in fall.
The timber of the Himalayan and tropical Asian genusExbucklandia (by some authorities Symingtonia), which has two species, is much valued.
Angiosperms are plants that produce flowers and bear their seeds in fruits. They are the largest and most diverse group within the kingdom Plantae, with about 300,000 species. Angiosperms represent approximately 80 percent of all known living green plants. Examples range from the common dandelion and grasses to the ancient magnolias and highly evolved orchids. Angiosperms also comprise the vast majority of all plant foods we eat, including grains, beans, fruits, vegetables, and most nuts.
How are angiosperms different than gymnosperms?
The key difference between angiosperms and gymnosperms is how their seeds are developed. The seeds of angiosperms develop in the ovaries of flowers and are surrounded by a protective fruit. Gymnosperm seeds are usually formed in unisexual cones, known as strobili, and the plants lack fruits and flowers. Additionally, all but the most ancient angiosperms contain conducting tissues known as vessels, while gymnosperms (with the exception of Gnetum) do not. Angiosperms have greater diversity in their growth habits and ecological roles than gymnosperms.
How are angiosperms and gymnosperms similar?
As vascular plants, both groups contain xylem and phloem. With the exception of a very few species of angiosperms (e.g., obligate parasites and mycoheterotrophs), both groups rely on photosynthesis for energy. Angiosperms and gymnosperms both utilize seeds as the primary means of reproduction, and both use pollen to facilitate fertilization. Gymnosperms and angiosperms have a life cycle that involves the alternation of generations, and both have a reduced gametophyte stage.
angiosperm, any of about 300,000 species of flowering plants, the largest and most diverse group within the kingdom Plantae. Angiosperms represent approximately 80 percent of all the known green plants now living. The angiosperms are vascular seed plants in which the ovule (egg) is fertilized and develops into a seed in an enclosed hollow ovary. The ovary itself is usually enclosed in a flower, that part of the angiospermous plant that contains the male or female reproductive organs or both. Fruits are derived from the maturing floral organs of the angiospermous plant and are therefore characteristic of angiosperms. By contrast, in gymnosperms (e.g., conifers and cycads), the other large group of vascular seed plants, the seeds do not develop enclosed within an ovary but are usually borne exposed on the surfaces of reproductive structures, such as cones.
How different plants store their seedsVideo presentation describing the differences in seed storage between angiosperms and gymnosperms.
Unlike such nonvascular plants as the bryophytes, in which all cells in the plant body participate in every function necessary to support, nourish, and extend the plant body (e.g., nutrition, photosynthesis, and cell division), angiosperms have evolvedspecializedcells and tissues that carry out these functions and have further evolved specialized vascular tissues (xylem and phloem) that translocate the water and nutrients to all areas of the plant body. The specialization of the plant body, which has evolved as an adaptation to a principally terrestrial habitat, includes extensive root systems that anchor the plant and absorb water and minerals from the soil; a stem that supports the growing plant body; and leaves, which are the principal sites of photosynthesis for most angiospermous plants. Another significant evolutionary advancement over the nonvascular and the more primitive vascular plants is the presence of localized regions for plant growth, called meristems and cambia, which extend the length and width of the plant body, respectively. Except under certain conditions, these regions are the only areas in which mitotic cell division takes place in the plant body, although cell differentiation continues to occur over the life of the plant.
The angiosperms dominate Earth’s surface and vegetation in more environments, particularly terrestrial habitats, than any other group of plants. As a result, angiosperms are the most important ultimate source of food for birds and mammals, including humans. In addition, the flowering plants are the most economically important group of green plants, serving as a source of pharmaceuticals, fiber products, timber, ornamentals, and other commercial products.
Although the taxonomy of the angiosperms is still incompletely known, the latest classification system incorporates a large body of comparative data derived from studies of DNA sequences. It is known as the Angiosperm Phylogeny Group IV (APG IV) botanical classification system. The angiosperms came to be considered a group at the division level (comparable to the phylum level in animal classification systems) called Anthophyta, though the APG system recognizes only informal groups above the level of order.
Throughout this article the orders or families are given, usually parenthetically, following the vernacular or scientific name of a plant. Following taxonomic conventions, genera and species are italicized. The higher taxa are readily identified by their suffixes: families end in -aceae and orders in -ales.
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Dilcher, David L., Stevenson, Dennis William, Cronquist, Arthur, Berry, Paul E., Zimmermann, Martin Huldrych, Stevens, Peter. "angiosperm". Encyclopedia Britannica, 21 Apr. 2025, https://www.britannica.com/plant/angiosperm. Accessed 30 April 2025.
