The most commonly encountered drainage pattern is the dendritic pattern (Figure 5.23A). This pattern of irregularly branching tributary streams resembles the branching pattern of a deciduous tree. In fact, the word dendritic means"treelike The dendritic pattern forms where the underlying material is relatively uniform. Because the surface material is essentially uniform in its resistance to erosion, it does not control the pattern of stream flow. Rather the pattern is determined chiefly by the direction of slope of the land.
When streams diverge from a central area like spokes from the hub of a wheel, the pattern is said to be radial (Figure 5.23B). This pattern typically develops on isolated volcanic cones and domal uplifts.