Glehnia littoralis Seeds | Adenophora Slice Root Slice Radix
LATIN NAME: Glehnia littoralis
COMMON NAME: Adenophora Slice, Glehnia Root, Bei Sha Shen
Plant Profile
Glehnia littoralis grows on the front line of the coast, in loose sand above the tide line from Shandong and Liaoning down through Korea to the beaches of northern Japan. It is a plant of salt spray, buried stems and shifting ground, and it holds the dune together with a taproot that runs a metre or more below the surface.
The leaves are compound, thick and grey-green, lying almost flat in a rosette, and the flowers are small white umbels on stems twenty to forty centimetres tall. The root is the crop: pale, slender, brittle and sweet, lifted in autumn and peeled for the trade.
Science & Biotechnology
The root is an umbellifer root, and that brings furanocoumarins with it. Imperatorin, psoralen and bergapten have all been reported, which is why handling large amounts of fresh root in sun can produce a phototoxic reaction on the hands.
The Chinese market separates two drugs that are easy to confuse. Bei sha shen is this species; nan sha shen is an Adenophora, a campanula relative with a very different root. Both are sold as sha shen, and the substitution is common enough that pharmacopoeial identification relies on the furanocoumarin profile, which Glehnia has and Adenophora lacks. The root is also high in a sweet-tasting polysaccharide fraction, which is why a decoction tastes of cane sugar rather than of medicine.
Uses & Benefits
The dried root is decocted at nine to fifteen grams for dry cough, thirst and the dry mouth that follows a fever. It is a mild, sweet herb, usually combined with ophiopogon or mulberry leaf rather than used alone.
Cultivation in Shandong has expanded because wild dune populations are protected, but the root is still dug from the wild in parts of the range. Because the fresh root is phototoxic, gloves are sensible when peeling. There is no clinical trial literature of any weight, and the herb is not used where there is a productive cough with much phlegm. In Shandong the root is also candied and sold as a sweet, which is a food use with no medicinal claim attached.
Growing from Seed
Seed has an underdeveloped embryo, which means a warm period is needed for the embryo to grow before cold can break dormancy. Six weeks at 20°C followed by eight weeks at 4°C gives the best results; a straight cold stratification often fails.
Sow in deep sand, since the taproot forks if it meets stone, and keep the bed moist but never wet. Plants tolerate salt wind and poor soil but not competition from grass. Roots are lifted at two years, in late autumn, and the seed is best sown fresh, as it loses viability within a year.
Our Take
A dune plant with a delicate root and a real identification problem; worth growing for the challenge, and worth buying only from a seller who can name the species.
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