A plant community is a group or association of plant species that collectively create a relatively uniform patch within a specified geographical area, which can be distinguished from nearby patches of other vegetation types. Plant communities are often defined by dominant plant species, which provide useful habitat information for many animal species. They are studied substantially by ecologists, due to providing information on the effects of dispersal, tolerance to environmental conditions, and response to disturbance of a variety of plant species, information valuable to the comprehension of various plant community dynamics.

Plant communities can be described floristically (the species of flowers or flora the plant community contains) and/or phytophysiognomically (the physical structure or appearance of the plant community) . For example, a forest (a community of trees) includes the overstory, or upper tree layer of the canopy, as well as the understory, a layer consisting of trees and shrubs located beneath the canopy but above the forest floor.

Plant community structure is studied under phytosociology, which is the study of the structure and composition of plant communities. Plant community descriptions provide information about the standardized types of plant communities, which provide a common framework for ecologists, foresters, environmental planners, and others to use in a variety of ways, including land management and conservation planning.

The plant community elements are impacted by soil type, topography, climate, and human disturbance. The formation of soils through rock weathering and soil-organisms continues, and the thickness of soils continues to increase with time. Consequently, a few soil-living animals like mites, ants, spiders, etc. are evolved.