The Science of Biodiversity and Conservation

   Cultivation of Herbs

One suggested way to prevent the growing demand for herbal medicines from endangering herb species is the commercial cultivation of those species which are in high demand specifically for the purpose of selling them on the world market.

Though some experts on the subject of herbal medicines claim that cultivated herbs may not have the same properties as herbs grown in the wild, there is good reason to believe that most herbs can be successfully cultivated. This Canadian site provides information regarding the successful cultivation of Ginseng. This information can be view as highly important, as American Ginseng is now listed in CITES as threatened, and has been harvested a great deal in the States for the purpose of export to the East.

As this site points out, the American government currently pays subsidies to certain farmers in order to discourage them from planting certain crops. This is done because if too many small farmers were to compete with each other they may all find themselves required to charge prices so low for their produce that the agricultural industry will no longer be sustainable. If some of these farmers could be encouraged to cultivate herbs instead, the American agricultural industry would become more diverse, and less subsidies would be required to keep it sustainable.

Unfortunately, as pointed out by Michael T. Murray, in his publication, The Healing Power of Herbs, stringent FDA regulations placed on herbal medicines in this country discourage this type of cultivation from taking place. While in Germany, for example, herbs can be sold as medicines if they can be "proved to be safe and effective," in the United States, getting FDA approval of a plant-based drug "typically takes 10 to 18 years at a total cost of roughly $230 million dollars."

One specific example sited by Murray concerns extracts of an herb called Ginkgo biloba. While in Germany and France, this herb shows a combined annual sales total of over $500 million dollars as a treatment for cerebral and peripheral vascular insufficiency, in the United States it is sold as a "food supplement" and is considerably less successful commercially.

Another major reason for the limited practice of herb cultivation so far appears to be simply the lack of specific knowledge as to their medicinal properties. This is actually quite surprising, as about a quarter of all perscription drugs used in the US today are either taken directly from plants, or are based on chemically modified versions of substances taken directly from plants. Furthermore, over half of all perscription medicines are modeled on natural compounds. These include drugs are widely varied as the well known painkillers Codeine and Morphine, a treatment for malaria known as Quinine and a heart stimulant known as Digitalis. (Source)

In the last decade, it has become recognized that traditional uses of herbs often relate to actual medicinal properties held by those herbs. The practice of "ethnopharmacognosy" involves the interviewing of indigenous peoples regarding their traditional herbal medicines, and then targeting the plants they claim have medicinal properties for scientific research. Shaman Pharmaceuticals is one company that specializes in this practice.

Unfortunately, this addresses the problem of endangered herb species only very indirectly. As Murray points out, pharmacognosy generally involves the isolation of particular "active constituents" from plants. As such, if a company like Shaman Pharmaceuticals discovers that a certain herb can be used as a medicine, it is more likely to attempt to isolate the compounds within that herb which have medicinal properties and then try to replicate them in a lab then to actually promote cultivation of the herb. Murray also tells us that it has been "demonstrated with many plants that the whole plant or crude extract is much more effective than isolated constituents," a belief commonly adhered to by practitioners of herbal medicine.

In order to protect endangered herb species, then, it would be necessary to convince the government or the agricultural industry to promote the cultivation of herbs themselves (rather than synthetic drugs based on them), despite the fact that the FDA specifically prohibits companies which market herbs in this country from making any claims regarding their products' medicinal properties. This appears to be the main barrier to the practice of herb cultivation. The industry is simply not as yet recognized as important enough to warrant this type of large scale economic endeavor.