Flora

frame|right|Simplified schematic of an island's flora all its plant species, highlighted in boxes Flora (: floras or florae) is all the plant life present in a particular region or time, generally the naturally occurring (indigenous) native plants. The corresponding term for animals is fauna, and for fungi, it is funga. Sometimes bacteria and fungi are also referred to as flora as in the terms gut flora or skin flora for purposes of specificity.

In phytogeography, a phytochorion is a geographic area with a relatively uniform composition of plant species. Adjacent phytochoria do not usually have a sharp boundary, but rather a soft one, a transitional area in which many species from both regions overlap, called a vegetation tension zone, or ecotone.

Megaflora (from Greek μέγας megas "large" and Neo-Latin flora "plant life") refers to an exceptionally large plant species; Jared Farmer defined the term as "the largest vascular plants of a particular region, habitat, or epoch". Examples of megaflora include the Sequoioideae of California, Pando (a large clonal organism of quaking aspen located in Utah), and a number of extinct plant species from the Mesozoic.