Plant Portraits 18. Plants that Heal.

  (Note images in this series were generated with the assistance of modern AI tools. No actual human individuals are portrayed here. See the first installment of the series for further explanation)

 Plants cannot run or fight, and so have adopted varied means of passive defense. Some have spines, prickles or thorns, others feign wilting upon contact, or disguise themselves as rocks. Grasses have extraordinary resprouting ability, and largely regrow themselves after being gnawed upon by grazing animals. the most common plant defense, however, is the production of "secondary plant compounds' which either deter or poison would-be browsers. One man's poison, however, is another man's medicine (or spice!). Plant poisons, in the right dosage often have healing properties in the human body.

Plants, in fact, are the original basis of most traditional medicines, and still account for about 25% of modern medical compounds. Nearly 30,000 species have been recorded as used  historically by ethnic groups worldwide, so this post is only a very brief introduction to this herbal storehouse. 

The use of medicinal plants predates humanity. Chimpanzees, seen here folding and 

swallowing Aspilia leaves for stomach discomfort, have been documented to use 26 species

 in their native range. Elephants, Orangutans, and a scattering of other animal 

self-medication have also been documented. 

 

 

The bark of willow trees (genus Salix) contains salicin acid, the root ingredient in aspirin 

(after conversion to acetylsalicilic acid). It was independently discovered in different areas of the 

world where willows grow. Here an indigenous American woman prepares strips of willow bark 

to be chewed by a young girl suffering from a headache.

An indigenous  woman in southern Africa treats her child's burned arm with the soothing sap  

of Aloe vera. In modern times this species is used for a variety of skin care products as well as 

consumption of its edible leaves and juice for a variety of putative health benefits.  

Altogether, an estimated 5000-6000 species of African plants have documented medicinal use,  

nearly 4000 in in the ecologically diverse region of southern Africa.

The use of plant remedies has been extensive throughout the long history of China. The first 

recorded documentation was in the the Shennong Bencao Jing (Divine Husbandman's Classic 

of Materia Medica) during the Eastern Han Dynasty in the first or second century CE. 

This, however, was based on more than 2000 thousand years of tradition that had been 

handed down orally and sporadically documented in writing. That compendium listed only 257  

species of plants, but an estimated 2500 species have been documented for common usage  

in ancient China, with an additional 2500 species noted for occasional use. Here, a young 

woman returns from gathering wild medicinal herbs in the mountains to a pharmacy workshop. 

In the foreground are trays of ginseng ((Panax ginseng) drying in the sun, Ginseng is perhaps 

the most famous, popular, and expensive of Chinese herbal medicines, with a wide 

variety of putative health-enhancing benefits. 

In an early European pharmacy workshop, people are processing leaves of  Foxglove 

(Digitalis spp.), which can be seen growing in the garden in the background. Digitalis is 

a powerful heart stimulant that can be fatal if taken in excessive dose. 

  

 

In Australia, indigenous peoples throughout the continent have traditionally used an estimated 

1500 native species for medicinal purposes. Here eucalyptus leaves are being boiled to create 

vapor rich in the volatile oil eucalyptol to relieve symptoms of respiratory ailments in an 

infected child. 

The active ingredients in Cannabis sativa (Marijauna) are much in the news these days as 

societies grapple with how to regulated medicinal and/or recreational use. In this reconstruction 

the hallucinogenic effects of Cannabis smoke are employed in a religious ritual by prehistoric

 people in what is now northeastern China. Other evidence of early use has been found as 

well as in regions of central Asia.