Narrative

Land claptrap or ground burnout (Tribulus terrestris) is an annual native to Europe. This species is widely established in North America from eastern seaports west to Illinois and Nebraska. This species is also found in the Pacific Coastal region of North America. It has also become established in Mexico. It has leaflets in 4-8 pairs with solitary flowers.

The yellow color will help identify this lifeform. This lifeform is locally common. This lifeform is sometimes considered an undesirable species.

This lfieform is found in Europe. This lifeform is widespread in North America. This lifeform is found in Mexico.

Tribulus genus is found worldwide in tropical and warm regions. There are about 25 herbs and shrubs in this genus. Many of the species are prostrate or low growing. The leaves are evenly pinnate with entire leaflets. The axillary flowers are yellow. There are two species established in North America. Both of these species were named by Linnaeus.

Caltrop Family (Zygophyllaceae) is a small tropical family of less than 300 species with 18 representatives in seven genera found in the southern United States.

Geranium Order (Geraniales) is a large order composed of many different families. Included here are the Geranium, Oxalis, and Citrus groups.

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.