Pawale are often unremarkable shrubs or vines, but they can occasionally have colorful floral displays. They are numerous and conspicuous on some lava fields, but sparse in the forests. Rumex is the only Hawaiian genus of family Polygonaceae.

Alien sheep sorrel is also extremely common in Hawai'i, and polygonum capituatum (persicaria capitata) is a widespread and potentially problem invasive.