How to distinguish azaleas in the wild?

There are many varieties of rhododendrons, which are mainly classified according to their colors. The white one is called Yingshan White, the purple one is called Yingshan Purple, and the yellow one is called Yingshan Yellow. These names are distinguished by local people according to their colors, because they look the same, but the colors of flowers are different. But except azaleas, other species of azaleas are very rare, so most people call azaleas azaleas.