Identifying plants by their names
Common names place plants in the everyday world because their names are easy to remember and usually easy to pronounce. Some names are descriptive—monkshood, bloodroot, bleeding-heart, goldenrod, jewelweed. Others indicate a plant’s use. Boxwood was used to make decorative boxes; woundworts, to treat wounds; chaste tree, to ensure chastity; crampbark to ease stomach cramps; fleabane to ward off fleas; lungwort to treat lung ailments.
For all their beauty and simplicity, however, common names can be a source of extreme confusion. Some plants have more than one common name. Artemisia abrotanum, for example, is known variously as southernwood, old man, lad’s love, and garde-robe. You may know Valeriana officinalis as either valerian or as garden heliotrope. Confusion is also rife when two or more disimilar plants share a common name.
Understanding the basics
The binomial (“two-name”) system that botanists use for classifying and naming plants was devised by Carolus Linnaeus, an eighteenth-century Swedish biologist and botanist. It describes patterns of relationship and provides a means of organizing the complexity of nature.
The first part of a plant’s name gives its genus, the group to which it belongs and with which it shares many features. Both garlic and onions belong to the genus Allium. A plant’s species name consists of the genus name and a specific epithet, which indicates a group of individuals that have common attributes and can breed together. Garlic belongs to the Allium sativum species while onions belong to the A. cepa species. The abbreviations of the genus name to the first letter, as in A. cepa for Allium cepa, is used only when the genus is clear. Names enclosed in single quotation marks following species names indicate a single cultivated variety, or cultivar. Lady lavender’s botanical name, Lavandula angustifolia, is often followed by its cultivar name, ‘Lady’, on nursery identification tags.
Many generic names come from the names of mythological figures, such as Achilliea (yarrow) for Achilles and Artemisia for Artemis.
The importance of botanical names
For gardeners, knowing the Latin name of a plant is useful to ensure the identity of what is planted. For those who use herbs medicinally, however, knowing the exact identity of a plant is crucial. To benefit from a medicinal herb, you need to be certain you are using the right plant. Pot marigold, also known as calendula (Calendula officinalis), for example, has a long history as a soothing treatment for skin irritations, whereas the popular garden flowers called marigolds (Tagetes spp.) are not effective for this purpose.
Even more important, you must use the correct plant to avoid poisoning yourself or others. What Texans call buttercup is Oenothera speciosa, a member of the evening primrose family that has edible petals. The buttercup of New England is a member of the ranunculus family and is poisonous. To confuse matters even further, evening primrose (O. biennis) is a plant with a long history of traditional medicinal uses, and its essential oil is currently used as a dietary supplement and to alleviate symptoms of premenstrual syndrome. Only the Latin name will assure that you are using the correct plant.
Adapted with permission from Herbs for Health January/February 1997.
Test your botanical wisdom
Do you know for whom or what the following genera were named?
Answers to Botanical Wisdom Test
1. Asclepius (Greek, Asklepios; Latin, Aesculapius) the Greek god of healing
2. Narcissus, in Greek mythology, a beautiful youth who fell in love with his own image, killed himself when he couldn’t reach the person he saw reflected in the water, but was then turned into a narcissus plant
3. Captain Meriwether Lewis (1774-1809), American explorer
4. Daphne, in Greek mythology, a bashful nymph who, when pursued by Apollo, prayed for help and was turned into a laurel tree
5. Iris, the Greek goddess of the rainbow
Herbal Wreath Winner
I had an outside wedding on August 5, 2000. I decided to plant Black-eyed Susans along the stone wall path in honor of my husband’s sister, Susan, who died. ‘Susan’ decided to bloom the morning of the wedding! She was with us, giving us her spirit of sunshine and beauty.