Disambiguation of Some Common Plant Names

I think the word disambiguation is cute. It means to remove uncertainty, and in this context and Google's, to point out when two different things have the same name and clarify which is which. Scientific names were created to address this problem in plants and animals, but not everyone understands this and certainly not everyone uses scientific names. 

Below are disambiguations for sage, hemlock, bergamot, and yam. (More in future posts)

sagebrush, Artemisia is not the same as culinary sage, Salvia

Sage. Culinary sage, Salvia officinalis is in the mint family (Lamiaceae) and comes from Eurasia. Another group of sages, also called sagebrushes, are plants in the genus Artemisia, in the sunflower family (Asteraceae) many native to western North America. The two groups have similar scents. This confusion is made more difficult because there are over 900 species of Salvia, native all over the world, of which only some smell like sage and are called sages. Similarly Artemisia has almost 500 species, including, for example the European plant wormwood (Artemisia absinthium) and the Asian herb sweet Annie (Artemisia annua) as well as many called sage. See blog post about these plants link

culinary sage, Salvia officinalis, in bloom

It is native to Europe where it has been used as a flavoring

and medicine for millennia.

white sage, Salvia apiana, is endemic to California,
This sage is sacred to Native Americans. 
It tolerates drought well but not frost.

big sagebrush, Artemisia tridentata (It gets much bigger than this).

                                                        Here, growing wild in Idaho

Artemisia pycnocephala, sandhill sagebrush
 flowering in a garden in San Francisco

Note on sages: Sage is a scent people know, so it is easily used as a common name or a descriptkion. Consequently, not all plants called sages are either Salvia or Artemisia: Google notes wood sage (Teucrium) and barometer bush (Leucopohyllum). However, botanical revisions that have expanded both Salvia and Artemisia, so that some "not-real-sages" have become "real sages", in particular Russian sage, long called Perovskia atriplifolia, has been reclassified as Salvia yangii.

Hemlock. In Europe, hemlock is Conium maculatum, a tall herbaceous plant in the carrot or umbel family, Apiaceae. It is a very poisonous plant. In North America, hemlock is a tree, Tsuga species pine family, Pinaceae. It is not poisonous. Conium is a genus of six species, native to Europe and north Africa. Conium maculatum was long ago introduced to North America and has widely naturalized. Tsuga has five species native to North American and four in eastern Asia but none in Europe. Settlers to North America named the tree after the umbel. Americans usually say poison hemlock when referring to Conium, in order to be clear.  Blog about these plants link

Conium maculatum poison hemlock
Alnwick Poison Garden, England

Conium maculatum poison hemlock, leaf

western hemlock, Tsuga heterophylla, in Seattle Washington

Bergamot. Three different plants have bergamot as their common name. The bergamot that flavors Earl Grey tea is a citrus fruit (Citrus bergamia, lemon family Rutaceae), call it bergamot orange for clarity. The bergamot name began with a fat round pear (Pyrus communis, rose family Rosaceae), now very hard to find. The citrus fruit looked like it. The third bergamot, the most common one, is an American native plant in the mint family (Lamicaceae), Monarda fistulosa, also called wild bergamot. Apparently the smell of Monarda reminded colonists of the citrus fruit.  link 

bergamot orange, Wikipedia

Monarda fistulosa bergamot

Yam - Yams are plants in the genus Dioscorea in the yam family Dioscoreaceae. They are vines, often with edible tubers, found all over the world in the tropics. Of some 600 species, only two species are native to continental North America and a third has naturalized in a couple southern states. In the United States, since "real" yams are rare, the word yam is commonly applied to sweet potatoes,  Ipomoea batatas (in the large morning glory family Convolvulaceae), a vine with similar-looking leaves and an edible tuber. Sweet potatoes are native to the New World, though they were traded across the world long ago, even reaching Hawaii before the Europeans. There are many varieties of sweet potatoes, with different leaf shapes and tubers in a variety of colors, shapes and textures. Apparently, African slaves in the United States used the word yam, which they had used in Africa for Dioscorea, on sweet potatoes, and, being a handy little word, it stuck. Odds are, in the U.S., the yam in the grocery store is botanically a sweet potato. 

yam, Dioscorea, with flower buds
they produce a cluster of small star-shaped flowers
link on Google

sweet potato, Ipomoea batatas
leaves often look like these

sweet potato, Ipomoea batatas
They have typical "morning glory" flowers; the three lobed leaves 
are a common horticultural feature. Sweet potatoes are often planted 
in ornamental baskets. 

The mixups caused by these shared common names are made worse today because we search the internet to learn about plants, usually using the common name. A lot of helpful websites, telling you how to use the plant as food or medicine, fail to mention the scientific name. That is unfortunate and dangerous. 

The young needles of the hemlock tree are edible, poison hemlock new leaves might send you to the hospital; the majority of online searches warned me of the confusion, but it is possible to search in a way that doesn't bring up a warning. 

There are so many sages that their chemistry varies a lot and some species in both Salvia and Artemisia are considered unsafe to eat. Other species just do not taste good. Substitute other sages for culinary sage, cautiously. Both groups are big, so I can only say, "clearly identify the plant before eating much." 

rosemary is Salvia rosmarinus
so you could call it a sage.
It has quite a different flavor from 
culinary sage

Making your own Earl Grey tea, the receipes call for oil of bergamot. Both the citrus and the Monarda are sold as "oil of bergamot" the Monarda sometimes as wild bergamot. I imagine wild bergamot Earl Grey tea doesn't taste like the commercial tea. 

Yams and sweet potatoes share the name because the tubers are used the same, so the consequences of getting the wrong one will probably be growing a plant that doesn't match expectations. I personally wouldn't eat the tubers if the plant didn't look right, but I'm pretty cautious. 

Alas, if you don't know two plants have the same name, you don't know there could be a problem.

I discovered these ambiguous plant names well after graduate school, usually in a moment of surprise: "What, this sage[brush] isn't the same as the spice in my kitchen?" The shared names are a window into the past, showing us how people, finding a new plant, gave it a familiar name, based on some perceived similarity. 

Listen for the descriptors: sagebrush, poison hemlock, wild bergamot, Ghanian yam, Chinese yam--those are used to reduce confusion and, for safety and clarity, are not optional.

Comments and corrections welcome. 

Blogs I referred to above: 

Plant Confusions: Garden Sage and Sagebrush are Different 2013 link

Plant Confusions: The Three Bergamots. 2016 link

Plant Confusion: Hemlock Both Umbels and Conifers 2013 link

Related and Unrelated Plants: Sweet Potatoes, Morning Glories and Yams 2013. link

     more about sweet potatoes: Plant Story: Sweet Potatoes, Ipomoea batatas 2023. link

Kathy Keeler, A Wandering Botanist
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