Wednesday, March 6, 2013

Disaster! A star by any other name...

Aster pattersonii
 
This innocent looking tuffet above is a particularly well grown specimen in a garden, which is pictured in the wild in the next two images...scroll down to the last two and you shall see a tale of woe! A compact, perennial, alpine aster found on two or more peaks in the Front Range has somehow disappeared under the same name as a universal biennial weed from lower elevations: what used to be Aster bigelovii has swallowed up a distinctive taxon we are wont to call A. pattersonii: lumped by a botanist who may not have seen the latter in the wild, and certainly never grew it. Both names were synonymized as Machaeranthera bigelovii for many years, now resting (rather uneasily perhaps) under the name "Dieteria bigelovii (A.Gray) D.R.Morgan & R.L.Hartm." which I have yet to see in any field guide or Floristic manual.
 
Aster pattersonii on Mt. Goliath
 Taxonomists might well be accused of a Dis-Aster: the once relatively recognizable genus filled with starry composite blossoms has been rent apart by the wild-eyed gene-jockeying metataxonomists who have been cheerfully juggling our familiar names with cladistic and sadistic pleasure. Horticulturists have been racking their brains memorizing Almutaster, Canadanthus, Doellingeria, Eucephalus, Eurybia, Ionactis, Oligoneuron, Oreostemma, Sericocarpus and Symphyotrichum...and even more names--as you will shortly see. What's in a name? Quite a bit as we shall see...
 
Enjoy this poor little plant as it looks at treeline on Mt. Evans--charming and petite (much smaller than its heaped up synonymous names!)
 
Aster patersonii closeup (in the wild)
 This is the whole plant--believe it or not (including a small basal tuft of toothy foliage: needless to say, this is of great interest to rock gardeners: if one could only figure out what we should call it!


Closeup of Aster bigelovii
 
Here is a photograph of supposedly the same taxon: a wiry, (often tall) biennial universal in the Southwest where it makes masses of color in the autumn: take a look at the type specimen--and compare it to the spring blooming, perennial alpine at the top: Hello there, Mr. generic Taxonomist! Have you ever heard of ecotypes? Have you ever heard of distinctive morphology and distinct geographical distribution? I have no doubt that if you were to put both these plants in blenders, you are likely to have a rather similar slime result that may look awful similar if you did some genetic poking and prodding (although I can assure you that there must be a few pretty significant genetic distinctions to produce plants of such glaring morphological, ecological, geographical and just plain visible disparity.)
 
Aster bigelovii flower (closeup)
I am conjuring a clever young meta-meta-taxonomist of the future who will have determined that the far flung genera that were once split off of Aster are perhaps justifiably treated as mere subgenera or tribes (as it were) within the comfortable skirts of the mega-(but real) genus Aster. Perhaps that self-same genius shall discover that there are some subtle, yet distinct genetic markers that allow one to segregate the high altitude, perennial race (localized on just a few high peaks of the Front Range) as the distinct species Aster pattersonii. You will forgive me if I adhere in advance to the visionary taxonomy of my imaginary botanist! These names (however fuddy duddy) make a bit of sense. You, however, are welcome to call either (or both) "Dieteria bigelovii (A.Gray) D.R.Morgan & amp; R.L.Hartm." (Excuse me as I guffaw!)...
 
 

7 comments:

  1. Panayoti,

    Your dilemma reminded me of a paragraph in a book I have been reading/referencing titled, “Phlox: A Natural History and Gardener’s Guide” by James H. Locklear. I am sure you are familiar with the book since you are listed in the acknowledgements. I am including the paragraph below because it seems pertinent.
    “The only real challenge to Wherry’s determinations came from Arthur John Cronquist, a plant taxonomist associated with the New York Botanical Garden. Cronquist greatly annoyed Wherry by his treatment of Phlox in Vascular Plants of the Pacific Northwest (part 4, published in 1959), in which he disregarded a number of Wherry’s species and subspecies, tossing them into “subjective synonymy.” Wherry contested many of these in a series of papers published in the 1960s in which he did little to hide his irritation. Cronquist repeated many of these plus did some more lumping in his treatment of Phlox in Intermountain Flora (volume 4), published in 1983, a year (mercifully) after Wherry’s death. Both of these became highly regarded reference works and Cronquist’s views on Phlox were generally accepted and repeated. But, as will be seen in this present treatment, my experience in the field has shown that in many cases it was Wherry who got it right.”
    I hope the fact that disagreement in taxonomy is not really disaster, but simply business as usual gives you some solace. I refer to comprehensive references covering vast areas frequently. However, I do this always knowing to check sources from local authorities whose field experience typically makes their assessments more accurate.

    James

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    Replies
    1. Sorry not to get back to you sooner, James. I've been in Southern California for a blissful week. I think what Jim Locklear describes is very comparable to our poor neglected Aster: people only see what they already know and vice versa! Hard to get them to see something new!

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    2. Panayoti,

      I always appreciate your kind responses. Especially, considering other people involved with Rock Gardening Organizations do not respond. I guess no response is better than when the NARGS allowed two members to very publically ridicule my garden. Then they somehow got me removed from their sister organization, SRGC, without any reason. Maybe you should become the president of the NARGS and change the organizations intolerant culture.

      James

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  2. Asters get their name from the Latin word for "star," and their flowers are indeed the superstars of the fall garden. Some types of this native plant can reach up to 6 feet with flowers in white and pinks but also, perhaps most strikingly, in rich purples and showy lavenders.

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  3. Regarding "Aster patersonii," I am unable to find that name in the USDA Plants Database, in the Tropicos database, or in the International Plant Names Index database. A Google search for the name "Aster patersonii" reveals only one occurrence of that name on the Internet--your blog post. The name, Dieteria bigelovii, however, does appear in all of the aforementioned databases and it appears in floristic manuals. It appears in Flora of North America, Volume 20, published in 2006. It is also used in Checklist of Vascular Plants of the Southern Rocky Mountain Region, Version 3, published in 2009. And it is used on the web site, Southwest Colorado Wildflowers.

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  4. The majority of the splinter genera that you mention (Almutaster, Canadanthus, Doellingeria, Eucephalus, Eurybia, Ionactis, Oligoneuron, Oreostemma, Sericocarpus and Symphyotrichum) were not created by wild-eyed metataxonomists juggling familiar names with cladistic and sadistic pleasure. Rather, they are the result of astute observations by such botanical luminaries as Nees, Nuttall, Cassini, Greene, and Small in the 1800s and early 1900s. It is a testament to their genius that they were able to discern differences in these genera without the benefit of molecular genetic analysis and that modern genetic studies have vindicated their circumscription of the genera of North American Astereae (the Aster subtribe of the Asteraceae). It is unfortunate that, by implication, you have chosen to insult these North American botanists. The true nonsense lies not with botanists such as Nees, Nuttall, Cassini, Greene, and Small who realized that the genus Aster was an artificial assemblage of superficially similar plants not at all closely related to the true Old World Aster species. Rather, it lies in the botanists who followed them who lumped these disparate genera into a polyphyletic mega-genus. You should be celebrating these botanists whose astonishingly insightful observations have been confirmed by the analysis of genetic molecular markers.

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  5. The splitting of the genus Aster into segregate genera was not an arbitrary action by splitters gone mad. It was done to solve a problem. And this is the problem: outside of Europe and Asia, Aster species are more closely related to other genera that share the same geographic region than they are to European and Asian species of Aster. For example, the former North American Aster species are more closely related to North American genera such as Solidago and Chrysothamnus than they are to Old World Aster species. In other words, former North American Aster species are as different from Old World Aster species as Solidago and Chrysothamnus are from Old World Aster species. Lumping genetically unrelated plants together into one mega-genus, whose various subgenera would be more closely related to other genera than they are to true Old World aster species, is at least, if not more so, as crazy as the "splitting" that you rail against.

    If the New World "asters" are lumped in with the true Old World asters, then why not also lump in Solidago, Chrysothamnus, Erigeron, Conyza, etc.? After all, the New World "asters" are more closely related to the aforementioned genera than they are to Old World true asters. Why arbitrarily pick one group of species, those that superficially resemble Old World true asters due to convergent evolution, to unite into your mega-genus Aster and leave out other genera to which the New World "asters" are more closely related to?

    I do not the see enormous differences between "Aster patersonii" and Machaeranthera bigelovii that you do. Certainly, they are more similar than an African pygmy and a tall, Scandinavian blue-eyed blonde. If these two extreme human ecotypes can comfortably reside within the same species, I don't see what's so disastrous about a dwarf, perennial alpine ecotype being the same species as a widespread, short-lived lower elevation species. Or do you propose that human beings are unique and that no other species exhibits as wide a phenotypic variation as human beings?

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