Although short, most rivers in Taoyuan Hsien wind their ways into the ocean. The winding flow creates a vast tidal area at their outlets. After the tide ebbs, muddy or sandy shoals become visible. Water remains in the lower areas. This is another important wetland in Taoyuan Hsien in addition to the ponds. Red Forest is the most important plant in this wetland.

Red Forest belongs to the Red Forest family. Its skin contains rich Tannic Acid, an important raw material for red dye. Red Forest refers to the evergreen bush growing in the tidal outlets under tropical weather and sub-tropical weather. The salty land of tidal outlets are short of oxygen. Most plants cannot grow on there, except the Red Forest.

In addition to producing Tannic Acid and timber land, red forest resists waves, protects the shore, retains the soil, and resists winds. Most importantly, the viviparous Red Forest is the best example of the Nature's spectacular ability to adjust and cope with the environment. In addition, the primitive food-chain system created by Red Forest is the best means for education on environmental protection. As such, all countries strive to protect Red Forests .

In Taoyuan Hsien, the only Red Forest remains in the outlets of Shin-wu Creek and She-tzu Creek. She-tzy Creek does not have much Red Forest. The outlet of Shin-wu Creek is the only place where people can still Red Forest.