Common names can be a source of confusion. Frequently the same plant has more than one name: butterfly weed, for example. Because it was once used to treat pleurisy, butterfly weed is known by pleurisy root in some areas. Bouncing Bet, a common roadside wildflower brought to America by European settlers, is also known as soapwort: its leaves and rhizomes boiled in water make a lather for laundry and bathing. But, not so fast, other names for bouncing bet are fuller's herb and lady's washbowl...hmmm. Just as confusing as having a plant with more than one common name is having the same name applied to two or more different species. Marigold for example: Calendula and Tagetes share this common name.
To avoid such confusion, scientists use a standardized two-part naming system called binomial nomenclature.The first part of the plant's name gives its genus, the group to which it belongs and which it shares many features. The second part of the plants name tells it species-the particular kind of plant in the genus such as Rosa multiflora is the specific name for the mutliflora (many-flowered) rose. Also, the second (species) part of the name more often than not, describes something specific about the plant. Sometimes it tells the color of a plant's flowers; alba for white, rubrus for red, purpureum for purple. Or it may describe foliage; grandifolia for large leaves, rotundifolia for round leaves, millefoliium for thousand- or many-leaved. Or it may describe some other salient characteristic, erectus for upright, hirsutum for hairy, odorata for fragrant, myrtilloidies for myrtlelike. Some species names describe where a plant is typically found; montana- on the mountain, maritima- by the sea, aquatilis- in the water. And others tell how people have used the plants; edulis for edible, cathartica for cathartic and so on.
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