When pain or injury or disease struck, early man had little choice but to turn to plants. Developed empirically, by trial and error, many herbal treatments were nevertheless remarkably effective. Then medicine became more theoretical. The belief arose that the harsher the treatment, the better. Herbal medicine fell out of favour, branded as ignorant superstition. Change came only when formal medicine opened its doors and let the light of modern science shine in. Now, the new medical science is reaffirming much of the old herbal lore and extending the horizons of botanical 
medicine.
In these days of fast foods, plasterboard houses, and synthetic clothing, which of us does not long to return to a more natural way of life? No longer a back-to-nature fad but a growing philosophy, this wish to put nature back in our lives applies above all to those two most important of human concerns: getting healthy and staying healthy.
From the immemorial man has relied on plants to treat sicknesses and soothe aches and pains. The same herbs, trees, and shrubs employed by ancient people have continued to be valued through the ages – by the Egyptians, Greeks, and Romans, by apothecaries and physicians in the Middle Ages and later, by the settlers who came to North America, by Indians who met them there, and even by our own grandparents. Many of these plants are still used today; nearly half of all medicines currently prescribed are derived from members of the plant kingdom.
Over the ages, many magical and mystical powers were ascribed to such plants. Occasionally these beliefs were mere superstitions; more commonly they were based on keen observation. For although people knew that certain plants had indisputable healing powers, they could not 
explain how the plants’ medicinal powers worked, and so attributed them to supernatural forces. Today we understand many of the underlying physical and chemical principles that account for the medicinal properties of plants. Yet plants still do possess a magical quality – their beauty and the astonishing variety of their forms.
Plants are the basis upon which all other life depends. Humankind relies, directly or indirectly, upon the plant kingdom for oxygen, fuel, medicines, food and micronutrients, clothing and building materials as well as for many other necessities. Moreover, since prehistory, people have not only drawn upon plants for their value but have also imputed to the plant world sentiments which are religious, aesthetic, poetic and moral. As indicated by Mendel’s hereditary experiments with peas or Pasteur’s development of the germ theory of disease using yeast, plants play a significant role in the development of human knowledge.
Perhaps the most extensive investigation of medicinal plants has been in the Chinese, Ayurvedic and Thai medical systems. In each of these traditions, the use of herbs is governed by complex worldviews and explanatory models of the human body and its relationship to the universe. 
Herbal medicine is the oldest and most widely used form of medicine in the world. The cultural diversity of herbal traditions conceals many common trends that reach back into antiquity.
In the last few decades a curious thing has happened to botanical medicine. Instead of being killed off by medical science and pharmaceutical chemistry, it has made a comeback. Botanical medicine has benefited from the objective analysis of medical science: while fanciful and emotional claims for herbal cures have been thrown out, herbal treatments and plant medicines that work have been acknowledged. And herbal medicine has been found to have some impressive credentials. No laboratory has yet produced a substitute for digitalis. The penicillin that replaced mercury in the treatment of syphilis and put an end to so many of the deadly epidemics comes from plant molds; it was discovered accidentally as it destroyed a bacterial culture that Alexander Fleming was trying to grow in his laboratory. Belladonna still provides the chemicals used in ophthalmological preparations and in antispasmodics used to treat gastrointestinal disorders. In fact, plant substances remain the basis for a very large proportion of the medications used today for treating heart disease, hypertension, depression, pain, cancer, asthma, neurological disorders, and other ailments.
In ancient times, garlic was looked upon as almost a cure-all, prescribed for a multitude of ills, including cardiovascular disorders. Today, Ozark herbalists in the rural areas of Missouri’s Ozark Mountains continue to prescribe it to lower blood pressure. The juice of the aloe vera plant, an ingredient in many suntan and skin lotions, is squeezed on burns to sooth and promote healing, and on poison ivy to stop itching. Mullein is smoked as a decongestant. The milky juice of wild lettuce is recommended to make a wart fall off. The inside bark of the slippery elm, dried and pounded to powder, is used to make a drink to sooth the throat and stomach. Violet leaves are used to make a “blood purifier”, and dandelions are prescribed for kidney trouble.
In New Mexico, curanderos and curanderas use the manzanilla, a local chamomile, to treat colic and other infant ailments. They make a tea of yerba buena, a mint, to treat stomachache. A salve of comfrey is applied to pimples. A dandruff shampoo is made from yucca root. The osha root is chewed for toothache, headache, and indigestion; made into a poultice for sores; brewed into a tea for colds; and drunk prophylactically to prevent hangover. The curanderos’ pharmacopeia includes sage and purple sagebrush, Mormon tea, and many less generally familiar plants such as canutillo, mariola (an aster), and yerba de la negrita (a mallow), used to treat everything from rheumatism, urinary and kidney disorders, and congestion to skin ailments and fevers. They also mix wild cinnamon with plant called calabazilla to make a pesticide, claiming it drives insects and mice out of the house.
At the very southern tip of the Appalachians, in Alabama’s Cherokee County, a septuagenarian named Tommie Bass was dispensing a wide variety of herbal remedies in 1980’s. His visitors included professors who were impressed as much by Bass’s encyclopedic knowledge of the local flora as by his herbal teas such as catnip tea for headaches and calamus root for indigestion.
In China, the ancient tradition of using herbs to heal exist side by side with Western medicine. Since the Communists took power on the mainland in 1949, the government has had to deal with an acute shortage of trained physicians. It has encouraged the practice of “traditional” medicine.The paramedics, or “barefoot doctors”, who serve the rural areas are trained in traditional practice, which combines the use of medicinal plants with acupuncture to bring the yin and the yang back into balance. The use of ginseng as a tonic and panacea probably originated in China thousands of years ago. Chemical analysis has shown that ginseng contains a number of vitamins, minerals , and medically active substances called saponins. These would account for ginseng’s apparent ability to increase resistance to stress and to increase mental and physical capacity.
Like other counterparts in North America, Chinese herbalists use many cooking herbs in their medicine. Among these are mints, cinamon, orange peel, and licorice and ginger-roots (all used to treat headaches). Camphor and angelica are applied to bruises; alpinia berries are used to make a stomach powder; the tassel flower is used to treat fevers.
As these few examples suggest, there would appear to be much more to be learned from folk customs dealing not only with medicinal plants but also with many aspects of maintaining health and treating illness and disease.