The Fagales are an order of flowering plants, including some of the best-known trees. The order name is derived from genus Fagus, beeches. They belong among the rosid group of dicotyledons. The families and genera currently included are as follows:
The Vitaceae are a family of flowering plants, with 14 genera and around 910 known species, including common plants such as grapevines and Virginia creeper. The family name is derived from the genus Vitis.
Betulaceae, the birch family, includes six genera of deciduous nut-bearing trees and shrubs, including the birches, alders, hazels, hornbeams, hazel-hornbeam, and hop-hornbeams numbering a total of 167 species. They are mostly natives of the temperate Northern Hemisphere, with a few species reaching the Southern Hemisphere in the Andes in South America. Their typical flowers are catkins and often appear before leaves.
The Juglandaceae are a plant family known as the walnut family. They are trees, or sometimes shrubs, in the order Fagales. Members of this family are native to the Americas, Eurasia, and Southeast Asia.
The Casuarinaceae are a family of dicotyledonous flowering plants placed in the order Fagales, consisting of four genera and 91 species of trees and shrubs native to eastern Africa, Australia, Southeast Asia, Malesia, Papuasia, and the Pacific Islands. At one time, all species were placed in the genus Casuarina. Lawrence Alexander Sidney Johnson separated out many of those species and renamed them into the new genera of Gymnostoma in 1980 and 1982, Allocasuarina in 1982, and Ceuthostoma in 1988, with some additional formal descriptions of new species in each other genus. At the time, it was somewhat controversial. The monophyly of these genera was later supported in a 2003 genetics study of the family. In the Wettstein system, this family was the only one placed in the order Verticillatae. Likewise, in the Engler, Cronquist, and Kubitzki systems, the Casuarinaceae were the only family placed in the order Casuarinales.
The Ulmaceae are a family of flowering plants that includes the elms, and the zelkovas. Members of the family are widely distributed throughout the north temperate zone, and have a scattered distribution elsewhere except for Australasia.
Nyssaceae is a family of flowering trees sometimes included in the dogwood family (Cornaceae). Nyssaceae is composed of 37 known species in the following five genera:
The Strelitziaceae comprise a family of monocotyledonous flowering plants, very similar in appearance and growth habit to members of the related families Heliconiaceae and Musaceae. The three genera with seven species of Strelitziaceae have been included in Musaceae in some classifications, but are generally recognized as a separate family in more recent treatments such as the APG II system (2003). The APG II system assigns the Strelitziaceae to the order Zingiberales in the commelinid clade.
The Buxaceae are a small family of six genera and about 123 known species of flowering plants. They are shrubs and small trees, with a cosmopolitan distribution. A seventh genus, sometimes accepted in the past (Notobuxus), has been shown by genetic studies to be included within Buxus.
Asphodelaceae is a family of flowering plants in the order Asparagales. Such a family has been recognized by most taxonomists, but the circumscription has varied widely. In its current circumscription in the APG IV system, it includes about 40 genera and 900 known species. The type genus is Asphodelus.
Dilleniaceae is a family of flowering plants with 11 genera and about 430 known species. Such a family has been universally recognized by taxonomists. It is known to gardeners for the genus Hibbertia, which contains many commercially valuable garden species.
The Clethraceae are a small family of flowering plants in the order Ericales, composed of two genera, Clethra and Purdiaea, with approximately 75 species. They are native to warm temperate to tropical regions of Asia and the Americas, with one species also on Madeira.
Asparagaceae, known as the asparagus family, is a family of flowering plants, placed in the order Asparagales of the monocots. Its best known member is Asparagus officinalis, garden asparagus.
Begoniaceae is a family of flowering plants with two genera and about 2040 species occurring in the subtropics and tropics of both the New World and Old World. All but one of the species are in the genus Begonia. There have been many recent discoveries of species in the genus Begonia, such as Begonia truncatifolia which is endemic to San Vincente, Palawan. B. truncatifolia is smaller in size than other species of the genus Begonia and this new species is proposed Critically Endangered by standards set by the IUCN. The only other genus in the family, Hillebrandia, is endemic to the Hawaiian Islands and has a single species. Phylogenetic work supports Hillebrandia as the sister taxon to the rest of the family. The genus Symbegonia was reduced to a section of Begonia in 2003, as molecular phylogenies had shown it to be derived from within that genus. Members of the genus Begonia are well-known and popular houseplants.
Euptelea is a genus of two species of flowering plants in the monogeneric family Eupteleaceae. The genus is found from Assam east through China to Japan, and consists of shrubs or small trees:
Staphyleaceae is a small family of flowering plants in the order Crossosomatales, native to Europe, temperate and tropical Asia and the Americas. The largest genus Staphylea, which gives the family its name, contains the "bladdernut" trees. The family includes three genera with more than 40 known species.
Boryaceae is a family of highly drought-tolerant flowering plants native to Australia, placed in the order Asparagales of the monocots. The family includes two genera, with twelve species in total in Australia.
Hydrostachys is a genus of about 22 species of flowering plants native to Madagascar and southern and central Africa. It is the only genus in the family Hydrostachyaceae. All species of Hydrostachys are aquatic, growing on rocks in fast-moving water. They have tuberous roots, usually pinnately compound leaves, and highly reduced flowers on dense spikes.
Centroplacaceae is a family of flowering plants in the order Malpighiales and is recognized by the APG III system of classification. The family comprises two genera: Bhesa, which was formerly recognized in the Celastraceae, and Centroplacus, which was formerly recognized in the Euphorbiaceae, together comprising six species. The Angiosperm Phylogeny Group determined that based on previous phylogenetic analysis, these two genera formed an isolated clade and recognition of the family was "reasonable."
Peraceae Klotzsch is a family of flowering plants in the eudicot order Malpighiales. The family was segregated from the Euphorbiaceae by Johann Friedrich Klotzsch in 1859, and its uniqueness was affirmed by the Royal Botanic Gardens, Kew's Euphorbiaceae expert, Airy Shaw.
