Narrative

Winged pigweed (Cycloloma atriplicifolium) is found from Manitoba south to Indiana, Illinois, Nebraska, and Arizona. This 20-inch bushy annual is found along streams and occasionally as a weed on waste ground. The lanceolate leaves are acuminate at the apex and sinuate-dentate on slender petioles. The loosely flowered spikes are terminal panicles.

This lifeform is widespread in North America.

Cycloloma genus contains but one species. This species is native to North America. This annual herb is generally smooth.

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.