Editing Tributary (section)

==Ordering and enumeration==
Tributaries are sometimes listed starting with those nearest to the [[River source|source of the river]] and ending with those nearest to the [[River delta|mouth of the river]]. The [[Strahler number|Strahler stream order]] examines the arrangement of tributaries in a [[hierarchy]] of first, second, third and higher orders, with the first-order tributary being typically the least in size. For example, a second-order tributary would be the result of two or more first-order tributaries combining to form the second-order tributary.<ref name=FS/>

Another method is to list tributaries from mouth to source, in the form of a [[tree structure]], stored as a [[Tree (data structure)|tree]] [[data structure]].{{Citation needed|date=July 2011}}