There have been many systems of plant classification over the centuries, but until recently most were based on flower and fruit morphology. Starting in the late 1990s, the Angiosperm Phylogeny Group set out to devise a better system, one based on DNA analysis and phylogenetic (evolutionary history) studies. They’ve since published four systems, the most recent one this year.
As a result, some of the species in the guidebooks I mentioned in part one of this post – especially Newcomb’s – no longer exist. Not that the plants have become extinct, but they’ve been renamed. Sometimes two or three different species have been combined into one. Sometimes species have been moved into new genera, or even new families. (See this post from last October: Are Asters Really Asters?)
This makes using the internet problematic. If I’ve gotten a tentative ID from the books, the next thing I do is google the species name. If the search turns up a different name, then I know there’s been a change. For example, a google search of Sanicula gregaria yields 5 hits for Sanicula gregaria and five for Sanicula odorata on the first page, which is a clue. When this happens, I turn to ITIS (the Integrated Taxonomy Information System) to find the latest name; in this case S. gregaria is now called S. odorata. But I’ll search under both names for the information I want, since some sites don’t update frequently.
Once I have that sorted out, there’s another thing I want to check before saying for sure which species it is. As the real estate agents like to say, location, location, location. The guide books will say where a plant is found, but they can be vague, especially if you found the plant at one extreme of its range.
The USDA PLANTS Database is a good resource for taxonomic, conservation, and location information, but with a few caveats. First, they often use older botanical names (though this seems to be changing). Second, for Maryland many species are shown as present in the state, but there’s no data at the county level. Look at the page for S. odorata, for example; you’ll see dark green indicating where the plant can be found. But if you zoom in, you’ll see the whole state of Maryland is light green, indicating that there is no county data. So where in Maryland has it been recorded?
The state of Maryland has many different habitats, and plants that grow happily on the Eastern Shore probably won’t be found on the Appalachian Plateau, so having more specific location information is important.
Another good resource, better for this purpose, is the Biota of North America Program’s North American Plant Atlas, where you can see county level maps for each genus. Looking at the page for Sanicula, you can see tell quickly that four species are present in Maryland. Click on each map, and you can see that S. canadensis is present in most counties, S. marilandica is present in nine counties but rare, S. odorata is present mostly in the Piedmont counties (and some in the far west and some on the Eastern Shore), and S. trifoliata is present in only a few counties, and rare. If the plant in question was found in Howard County, I can say that it’s is unlikely to be S. marilandica.
A third resource is the ever-growing Maryland Biodiversity Project, which is adding new records by the dozens every day. I can’t say that it’s the final word, because absence of records does not equate to absence of a plant (it’s a work in progress.) From the home page, pull down the Plants menu, click on Browse by family, choose Apiaceae, then click on the word Sanicula in the Genus column, then click on each species to see a map of where they’ve been recorded, and usually photos.
(As an aside, I’ll going to brag a little: the MBP has only three photos for Scutellaria nervosa, and they’re mine.)
Once I’ve determined that a species does indeed grow where I’ve found it, I’ll go to Illinois Wildflowers for a detailed but not too technical description. Another good site is the New England Wildflower Society’s gobotany, which offers dichotomous keys and rather technical descriptions. Of course many Maryland natives aren’t found in Illinois or New England, but a lot are.
If I can’t narrow my search down any further, then I probably don’t have the right information. But there are other places where I can dig deep. More on that tomorrow.