The Science of Botanical Art

Economic Botany

By Dick Rauh 

Originally appeared in The Botanical Artist - Volume 16, Issue 1

 

Coming up for us is a major exhibition with The New York Botanical Garden. The subject is economic botany, and I thought it might be a good idea to expand and typify the plants that fit into this category. Although in the long run it sounds as if money is a factor in this division of plant identity, the basic definition stresses the usefulness of plants to people. 

Because of this, our primary concern about the beauty of a plant or flower, must take second place, and we are challenged to make the most of very important plants whose beauty may be hidden, while their value to the human condition is paramount. 

For a number of years I have been volunteering at NYBG for at the Institute of Economic Botany and it is fascinating. Led by Dr. Michael Balick, the scientists in this discipline spend countless hours in the field, investigating native uses of plants. But there is more to this sub-science, and attempts to codify the varied uses we find in the plant kingdom are extensive. 

Aside from the fact that we depend on plants in a general way for our very existence, the most obvious economic use is in the category of food. We humans are classified as heterotrophs, getting our sustenance second hand, either by eating the products of photosynthetic autotrophs (plants) directly, or through the animals that do. 

It is the vegetarian side of that formula we are concerned with here, although a perfectly legitimate class of economic plant comes in the category of forage, or plants grown for animal feed. How about a lovely painting of alfalfa? 

We tend to eat almost every part of a plant from the roots of carrots, beets or radishes, to tubers (potatoes), leaves (lettuce, cabbage), leaf stems (rhubarb ), stems (sugar cane, kohlrabi, taro), flowers and flower buds (artichokes, broccoli, cauliflower) and fruit (from apples to zucchini). Grasses provide some of the most important foods in the world. These rather unspectacular looking species supply the world’s populations with the staples of rice, wheat, corn and other grains, probably hitting the high points on the scale of economically important crops. 

Herbs and spices, are another category of comestibles, and open up huge possibilities for illustrating useful plants. Think of peppers, both Piper and Capsicum, cloves, nutmeg/mace, cinnamon. Plants are also the sources of many important flavorings, one of which is the vanilla orchid. This group of plants spurred exploration and exploitation for centuries- what more fitting classification of economic value. 

Another vast area to explore is perhaps the earliest one where botanical artists were needed. I speak of plants of medicinal value. Indeed the history of botanical art started with the need for clear, accurate portrayals of those plants that had therapeutic uses, so that practitioners would not be confused. Hence the herbals that were at the beginnings of medical science and botanical illustration. Many of the compounds found in plants have been duplicated chemically, as are the compounds within witch hazel. 

Yet, there is a history of traditional remedies and native cures that are still efficacious, and for an exhibit of this kind examples should be included whether the plants themselves are still harvested. Along with truly useful remedies the early herbals were full of plants that were listed because of the Doctrine of Signatures. These are plants thought to have specific cures for ills of a particular part of the body, based on clues visible in the growing plant. 

The mandrake with its root system resembling the whole body was thought to be a general treatment for human ailments. Heart-shaped or kidney shaped leaves were the clues to plants used to treat heart or kidney ailments. Maidenhair fern with its black rachis was thought to hold a cure for hair problems. In practice it was found to contain principles effective against asthma. Even today we are using Cinchona species as a source of quinine. Pacific Yew and Madagascar periwinkle are harvested in the fight against certain cancers, and I have barely scratched the surface. 

Stimulant plants are another possibility. Tea, coffee, cocoa all come from flowering plants, as do a number of narcotics. The opium poppy is a visual treat, especially its deadly pods, and the flowers of the plant that produces cocaine are a challenge. 

Many poisonous plants hold compounds that when used in moderation have proved vital cures instead of killers. Foxglove is an example of this as are the alkaloids of certain Solanum species. Such poisonous plants as the nightshade family Datura and Brugmansia while highly toxic, have been used in some cultures as hallucinogens.  

Then there are the plants that provide us with products useful to our lives. The mallow that is cotton with its silky haired seeds and flax from which we produce linen along with many other plants, are the sources of textiles and fibers. Wood is a viable plant part that is everywhere in use, lumber, furniture, tool handles, fuel, the list goes on and on. So it would seem we need some tree drawings to add to the economic botany list. Tannins and dyestuffs are another category of plant uses. Annatto whose pulp produces an orange color, and indigo, a traditional source of blue, are a couple of important genera supplying dyes for centuries. And tannins used in the tanning of leather have traditionally come from oak bark. 

I am certain I have left out a category or two in the areas of plant usefulness, but you get the idea. The value of plants to people is ubiquitous, even in this day of plastics and chemical dominance, somewhere out there is a plant of great economic value waiting to be painted. 

There are many books and websites devoted to economically important plants for you to research to find subjects. And more to the point most botanical gardens have areas devoted to growing plants of medicinal or other economic uses, where you are able to sketch and photograph living material. 

In order not to impede the flow of thoughts in the article I have decided to use common names in the text. Here are the Latin binomials in the order that they appear: Alfalfa – Medicago sativa; carrots - Daucus carota ssp sativus; beets - Beta vulgarus; radishes - Raphanus sativus; potatoes - Solanum tuberosum; lettuce -Latuca sativa; cabbage - Brassica oleracea Capitata group; rhubarb -Rheum spp; sugar cane - Saccharum spp; kohlrabi - Brassica oleracea Gongylodes group; taro/dasheen - Colocasia esculenta; artichokes -Cynara cardunculus; broccoli -Brassica oleracea Italica group; cauliflower - B. oleracea Botyritus group; apples –Malus domestica; zucchini – Cucurbita pepo; rice –Oryza sativa; wheat –Triticum spp.; corn – Zea mays; pepper – Piper nigrum; pepper – Capsicum annuum; cloves -Syzygium aromaticum; nutmeg/mace -Myristica fragrans; vanilla – Vanilla planifolia; cinnamon -Cinnamomum verum ; maidenhair fern - Adiantum spp.; Pacific yYew -Taxus brevifolia; Madagascar periwinkle - Catharanthus rosea; tea - Camellia sinensis; coffee - Coffea Arabica; chocolate - Theobroma cacao; opium - Papaver somniferum; cocaine – Erythroxylon coca; foxglove - Digitalis spp; cotton – Gossypium spp.; flax - Linum usitatissimum; annatto - Bixa orellana; indigo - Indigofera tinctoria; oak -Quercus spp 

  • Prunus persica, watercolor, ©Carol Hamilton 2004
  • Edible Greens, colored pencil for seed packet, ©Libby Kyer 2008