huāng cǎo
weeds
brush (vegetation)
wild grassland
Zhōu Yú dǎ Huáng Gài
fig. with the connivance of both sides
fig. by mutual consent
cf Wu patriot Huang Gai submits to mock beating at the hands of General Zhou Yu to deceive Cao Cao 曹操 before the 208 battle of Redcliff 赤壁之戰|赤壁之战[Chi4 bi4 zhi1 zhan4]