How do you pronounce Gomphocarpus physocarpus? What is it? And how can we ever remember how to spell it? What’s Aquilegia caerulea? You might know it as Colorado’s native Blue Columbine (right). Or how about Symphyotrichum novae-angliae? Isn’t it simpler just to say New England Aster? Scientific names are enough to drive gardeners crazy, so why in the world do we need to bother with them?
Scientific names, also called Latin names, can be annoying, but they serve a valuable purpose. We owe a huge thank you to Carl von Linné, the Swedish biologist who, back in the 1700s, invented what we now call binomial nomenclature. He also had the bright idea to use Latin, or at least to Latinize the words from another language, in order to avoid giving preference to any nationality. Scientists all around the world use the same Latin name to designate a particular species.
You probably learned the basic hierarchy in your biology class: Kingdom, phylum, class, order, family, genus, species. The “scientific name” includes those last two—the genus and species. The genus is always capitalized, while the species is not. Both are italicized.
Why do we need these pesky names? Let me give you one example. There’s a pretty red wildflower (right) that grows in the Rockies. It goes by the scientific name Ipomopsis aggregata. But that’s hard to remember. So instead, let’s use the common name. Which one would you like? It’s variously known as Skyrocket, Scarlet Gilia, Scarlet Trumpet Flower, or Sky Trumpet. If I’m talking about Scarlet Gilia, how will you know I mean the plant you know as Skyrocket?
Here’s another example. There’s an interesting plant with spinach-like leaves that’s native to the southwestern U.S. You might know it as Strawberry Blite, or Blite Goosefoot, or Strawberry Goosefoot, or Strawberry Spinach, or Indian Paint, or Indian Ink. Yes, those are much easier to say than Chenopodium capitatum, but if I use the Latin name, at least I know what we’re talking about!
Name confusion can work the other way around as well. If I say I just planted a cedar, do you imagine a huge tree related to the coast redwoods, or a small evergreen shrub? How about a plant in the pine family that grows in the Mideast? Or perhaps it’s one of those large, geometrically shaped evergreens that look like exclamation points in the landscape. Those are all “cedars” but only one is a “true cedar” in the genus Cedrus (the Cedar of Lebanon). What about the rest? The huge tree is in the cypress family, the small shrub might be a juniper, and the tall skinny evergreen is an Arborvitae.
It might surprise you that if you’re an enthusiastic gardener, you already know a plethora of Latin names. Rhododendron, Zinnia (left), Cosmos, Begonia, Fuschia, and Chrysanthemum are just a few of the plants we all know by their genus. Others aren’t so far from the familiar common names. For example, you should be able to figure out Lavendula, Rosa, Jasminum, and Pinus, to name a few.
It would be lovely if the story ended here—use the scientific name and avoid confusion. Unfortunately, that would be too good to be true. The world of botany is in the middle of a major upheaval due to the growing availability of genome mapping. Plants that happily lived in one genus for years are being suddenly uprooted and moved to a different genus. Taxonomists hope that the new names better reflect a plant’s relationship with its close relatives.
For example, Autumn Joy is a lovely stonecrop (right) that until recently was known as Sedum spectabile. When I went to look it up online, I found that it has suddenly become Hylotelephium spectabile. Now I have to go re-label all my photos.
This doesn’t sound too bad—the name changes and we all learn the new one. But things are worse than that, as you can see in this excerpt from The Guardian:
More than 600,000 plant species have been deleted from the dictionary of life after the most comprehensive assessment carried out by scientists.
For centuries, botanists from different parts of the world have been collecting and naming “new” plants without realising that many were in fact the same. The humble tomato boasts 790 different names, for example, while there are 600 different monikers for the oak tree and its varieties.
The result was a list of more than 1 million flowering plant species. Although experts have long known that it included many duplicates, no one was sure how many. Later this year, the study team, led by UK and US scientists, will announce that the real number of flowering plant species around the world is closer to 400,000.
Let’s go back to that pretty red wildflower. The “official” name is Ipomopsis but it has a pile of synonyms, including various subspecies classifications: Cantua aggregata, Gilia aggregata, Gilia aggregata aggregata, and Ipomopsis aggregata aggregta. I’m not sure the scientific name is much of an improvement over the list of common names!
Still, sometimes a scientific name can be an improvement over the vernacular. Remember the Gomphocarpus physocarpus back at the top of the page? It’s a plant in the milkweed family and, based on its bristled, balloon-like fruit, its common name is Hairy Balls!