Narrative

Garden Orache (Atriplex hortensis) is an Asian species that has become established in Europe and has occasionally escaped into North America. This annual can be up to almost eight feet tall. The cordate or triangular leaves can be over four inches long. This species was named by Linnaeus.

This lifeform is frequentlhy domesticated.

This lifeform is found widely in Eurasia. This lifeform is widespread in North America.

Atriplex genus contains annual or perennial herbs or low shrubs. There are between 100 and 120 species in this genus. The leaves are alternate, petioled, or sessile, but some may be opposite. Flowers are small and green in panicled spikes or axillary clusters. There are 81 species and 22 subspecies growing in greater North America.

Goosefoot Family (Chenopodiaceae) contains about 1,300-1,400 species organized into perhaps 100-120 different genera. These are annual or perennial herbs (rarely shrubs) with angled stems. The petal-less flowers are usually small and greenish. This family had 27 genera and 190 species growing in greater North America as of 1994.

Centrosperm (Centrospermae) order is a large order composed of several families.

Dicots (Dicotyledoneae Class) are the predominant group of vascular plants on earth. With the exception of the grasses (Monocots) and the Conifers (Gymnosperms), most of the larger plants that one encounters are Dicots. Dicots are characterized by having a seed with two outer shell coverings.

Some of the more primitive Dicots are the typical hardwood trees (oaks, birches, hickories, etc). The more advanced Dicots include many of the Composite (Aster) Family flowers like the Dandelion, Aster, Thistles, and Sunflowers. Although many Monocots reach a very high degree of specialization, most botanists feel that the Dicots represent the most advanced group of plants.

Seed plants (Phylum Embryophyta) are generally grouped into one large phylum containing three major classes: the Gymnosperms, the Monocots, and the Dicots. (Some scientists separate the Gymnosperms into a separate phylum and refer to the remaining plants as flowering plants or Angiospermae.)

For North American counts of the number of species in each genus and family, the primary reference has been John T. Kartesz, author of A Synonymized Checklist of the Vascular Flora of the United States, Canada, and Greenland (1994). The geographical scope of his lists include, as part of greater North America, Hawaii, Alaska, Greenland, Puerto Rico, and the Virgin Islands.

Kartesz lists 21,757 species of vascular plants comprising the ferns, gymnosperms and flowering plants as being found in greater North America (including Alaska, Hawaii, Greenland, Puerto Rico and the Virgin Islands.

There are estimates within the scientific world that about half of the listed North American seed plants were originally native with the balance being comprised of Eurasian and tropical plants that have become established.