Why do botanists often use the term division instead of phylum?

In the context of biological classification, the terms division and phylum represent the same hierarchical level of organization. The distinction is purely a matter of disciplinary convention: phylum is the standard term used in zoology, while division is the traditional term used in botany.123

This usage persists largely due to the independent historical development of taxonomic naming conventions within each field. Because each major group of plants and animals has its own unique taxonomic history, these traditional terms have been preserved by practitioners.3

In groups that overlap both fields, such as the Protista, the choice of term often reflects the organism's characteristics: "phylum" is typically applied to animal-like protozoa, while "division" is used for more plantlike protistan groups that are of primary interest to botanists.2