Xi He Liu
Botanical name: Tamarix chinensis
Common name: Tamarisk
Literal name translation: western river willow
Part used in Chinese medicine: stems and leaves
Major Chinese medicine actions:
Releases exterior, induces sweating, vents rashes
Photo Credits: (top to bottom)
Photo 1: Tamarix chinensis; 06/2008; author Dalgial; permission under Creative Commons
Photo 2: Tamarix chinensis; 06/2008; author Dalgial; permission under Creative Commons
Photo 3: Tamarix chinensis; 05/2007; author TeunSpaans; permission under GFDL
Photo 4: Tamarix pentandra; 08/2006; author Jerzy Opioła; permission under GFDL
Tamarix chinensis is very closely related to Tamarix ramosissima, Tamarix gallica and Tamarix indica. It is a small deciduous tree or shrub native to China. Tamarix trees are sometimes referred to as “Salt Cedar” as they grow in soil with high salinity or alkalinity, commonly found along floodplains, riverbanks, streams, marshes and salt flats. They can form dense thickets that extend for miles. Pictured above, the top 3 photos are of Tamarix chinensis and the bottom photo is of Tamarix pentandra, an acceptable variation for used in Chinese medicine as the herb Xi He Liu.
Native to China, the tree was introduced as an ornamental in the West in the 1800’s, and at present is considered an invasive, noxious weed in the U.S, Australia and the UK. The tree is very difficult to kill, withstanding almost any environmental condition including long periods of drought as well as up to 3 months of flooding. However, it is very dangerous in fires because its resinous leaves burn explosively.
Tamarix has a long, deep taproot, growing 30 feet or longer, and an extensive rhizome system that spreads widely, allowing the tree to withstand drought conditions once it is established. It has one of the highest evapotranspiration rates of any land growing shrub, meaning that it removes water from the soil and releases it through its leaves. It can cause extensive water loss in up to a 13-acre range, causing surrounding sites to become very dry and reducing stream flows. When faced with a drought situation, it survives due to this ability to take up water from a deep and wide area, as well as being able to shed its leaves and stop growing, becoming temporarily dormant, if necessary.
Growing and Propagation
The tree grows 6-20 feet tall, varying with water availability. It has pretty drooping juniper-like branches and blooms in March through September with large feathery clusters of small pink flowers. Fruits mature in late summer or autumn. A mature Tamarix can produce 600.00 seeds annually and it self sows aggressively from both seed and root sprouts.
It does best growing in full sun but may also establish in part shade, but not full shade. It generally does not begin to flower until its third year of growth. It tolerates and thrives in a wide range of soils, sun and water availability and is hardy to USDA zone 7.
Harvesting and Preparation
For medicinal use, the herb is generally used without special preparation. Good quality Xi He Liu consist of thin green twigs and leaves.