Bai Mao Gen (Lalang Grass Rhizome)

Name

Bai Mao Gen (Rhizoma Imperatae), recorded in the Shennong Bencao Jing.

Source and quality

Plant

The rhizome of the perennial herb Imperata cylindrica Beauv. var. major (Nees.) C. E. Hubb., family Poaceae.

Where it is grown

Throughout China.

Harvest

Collected in spring and autumn.

Smell and taste

Faint smell; sweet.

Better grade

Thick and white.

Processing

The fibrous roots and membranous leaf sheaths are discarded, then it is washed, dried in the sun, sliced and used raw.

Nature and action

Sweet and cold; enters the lung, stomach and bladder channels. Cools the blood and stops bleeding, clears heat and promotes urination.

When it is used

Bleeding from blood heat

Bai Mao Gen is sweet in flavor and cold in nature, and enters the blood system, where it clears heat to stop bleeding. It is therefore used for the various bleeding syndromes driven by blood heat. It is often used alone in decoction, or taken fresh as juice after being crushed, or combined with other blood-cooling hemostatics.

It is especially good at bleeding arising from fire and heat in the upper body. At the same time, because it is cold and descending, enters the bladder channel, clears heat and induces urination and guides heat downward, it suits hematuria and bloody strangury caused by damp-heat accumulating in the bladder. Where frequent hematuria is due to both deficiency and heat, it is combined with tonics, such as Ren Shen, Di Huang and Fu Ling in Mao Gen Yin Zi from Wai Tai Mi Yao.

Edema, heat strangury and jaundice

It clears heat and induces urination, which eases edema, relieves strangury, drains dampness and relieves jaundice. It is used as a single decoction or combined with other herbs that clear heat and eliminate dampness.

Separately, it is used for vomiting from stomach heat, because it clears stomach heat to stop vomiting, and for cough and wheezing from lung heat, because it clears lung heat to stop cough.

Dose

Decoction 15~30 g, doubled for the fresh herb. The fresh herb is better, and the fresh juice can be taken directly. Use raw, or dry-fried with charcoal when stopping bleeding.