Shen Collection, Upper Volume Radical: Grass (cǎo) Tu Kangxi stroke count: 16 Page 1049, Entry 02 Jade Chapters (Yupian) pronunciation: da (level tone). Pronounced same as tu (rising tone). Interpretation of Plants (Erya): Tu is knotweed. Note: This plant resembles red grass but is coarser and larger; it has fine thorns and can be used to dye things red. Compendium of Materia Medica (Bencao): Also called bitter staff. It is also known as spotted staff, sour staff, and tiger staff. Also from Interpretation of Plants (Erya): Tu is also called wei leaf. Commentary: It is a type of weed.