Plants, including trees, herbs, bushes, grasses, vines, ferns, and mosses, belong to the kingdom of life forms. They play a vital role in sustaining life on Earth by converting water and carbon dioxide into oxygen through photosynthesis. This process also produces sugars that serve as the primary source of energy for all living organisms. Additionally, plants contribute to the nitrogen fixation process, which generates proteins that are essential for life. Fossil records indicate that photosynthesizing organisms existed as early as 3 billion years ago. Plants have had a significant impact on evolution by producing the oxygen that made life possible on our planet. They not only released oxygen into the atmosphere but also played a role in the formation of soils and the release of nutrients through their root systems. Plants are indispensable for the survival of all living creatures on Earth. They provide vital life-support services and serve as a source of food, medicine, and various other resources. Currently, there are approximately 250,000 described plant species.

Our understanding of the number of plant species is not without flaws. According to the International Union for the Conservation of Nature’s Red List, approximately 54 percent of the plant species that have been evaluated are considered threatened, which amounts to 10,584 out of 19,738. Other estimates suggest that one in eight plant species globally is at risk of extinction, with the United States facing a figure of one-third. The Red List further indicates that 279 evaluated plants are currently under threat in the United States.