What is the difference between common bugloss and rehmannia? A quick guide to tell them apart
In rural areas, wild weeds can be seen everywhere, and many people think they are nothing but weeds, not realizing that some of them are useful, just like common bugloss and rehmannia, which can be used as traditional Chinese medicine. Below is an introduction tothe differences between common bugloss and rehmannia.
Difference one: different families and genera
Common bugloss, also called xidiezicao, xuejiancao, etc., is an annual or biennial herbaceous plant of the genus Bothriospermum in the family Boraginaceae, with a height of 10-30 cm. Rehmannia, also called dihuang, shengdi, etc., is a perennial herbaceous plant of the genus Rehmannia in the family Scrophulariaceae, with a height of up to 30 cm.
Difference two: different leaves
The leaves of common bugloss are oblong or oblanceolate, green, with slightly wrinkled-wavy edges, and both surfaces are covered with upward appressed strigose hairs or short stiff hairs. The leaves of rehmannia are ovate to long elliptic, green on the upper side, slightly purplish or purplish-red on the underside, with irregular crenate or obtusely serrate to dentate edges, covered with fine white hairs.
Difference three: different flowers
The flowers of common bugloss are solitary in the leaf axils or nearly axillary, the corolla is small, and the flower color is blue or pale blue, rarely white, covered with appressed hairs or stiff hairs. The flowers of rehmannia grow at the top of the stem, or almost all are solitary in the leaf axils, the corolla is larger, and the flower color is purplish-red outside and yellow-purple inside, densely covered with multicellular long soft hairs and long white hairs.
Difference four: different medicinal effects
The whole plant of common bugloss can be used as medicine; it tastes slightly bitter and is cool in nature, and has the effects of promoting diuresis and reducing swelling, detoxifying and relieving itching, and is often used for eczema, hemorrhoids, and swelling and pain of the anus. The fresh or dried tuberous roots of rehmannia can be used as medicine, and according to the processing method they are divided into fresh rehmannia, dried rehmannia, and prepared rehmannia. Fresh rehmannia is a heat-clearing and blood-cooling medicine, while prepared rehmannia is a tonic medicine.
Fresh rehmannia: sweet and bitter in taste, cold in nature, with the effects of clearing heat and promoting fluid production, cooling blood and stopping bleeding, used for damage to yin from febrile disease, crimson tongue and polydipsia, warm toxin macules, vomiting blood, nosebleeds, and sore throat.
Dried rehmannia: sweet in taste, cold in nature, with the effects of clearing heat and cooling blood, nourishing yin and promoting fluid production, used for heat entering ying and blood, warm toxin macules, vomiting blood, nosebleeds, damage to yin from febrile disease, crimson tongue and polydipsia, fluid damage and constipation, and sore throat.
Prepared rehmannia: sweet in taste, slightly warm in nature, with the effects of nourishing blood and enriching yin, benefiting essence and replenishing marrow, used for blood deficiency and sallow complexion, palpitations, irregular menstruation, metrorrhagia and bleeding, yin deficiency of liver and kidney, soreness and weakness of waist and knees, steaming bone and tidal fever, night sweats and seminal emission, internal heat and wasting thirst, dizziness, tinnitus, and premature graying of beard and hair.