Aster Dichotomous Key (Northeast US)

Nature Talk
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It is that time of year again!
Call me old school but learning from a field guide is still the best way to learn, and that goes double for asters. Between their similarities and the narrow window each year to learn in situ, I just do not have the skills needed to identify them on the spot, or think about which features to focus on.

Is there a good dichotomous key for Northeast aster species? Specifically Symphyotrichum species?

There is an excellent, but slightly out of date version I use for goldenrod species… this is along the lines of what I am looking for: http://libotanical.org/newsletters/0205.pdf

Thank you all!

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in the northeast, you can always go with the keys at the Native Plant Trust: https://gobotany.nativeplanttrust.org/dkey/symphyotrichum/ or https://gobotany.nativeplanttrust.org/dkey/symphyotrichum/#all.

for the entire US, you can use the Flora of North America key: http://floranorthamerica.org/Symphyotrichum, along with the species maps from BONAP: http://bonap.net/NAPA/TaxonMaps/Genus/County/Symphyotrichum to narrow down species in the area.

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Newcomb’s wildflower guide also has a good key for these. Definitely a worthwhile reference for other groups too.

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Yes I meant to mention the Newcomb’s guide… the one I have is out of date for this, and seems to leave out a level of detail for some species.

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I would avoid the FNA key - it’s pretty out of date by now, and it’s a mess to try to navigate (mostly because of the wide scope). The character-states are not well delineated. It’s a headache to contemplate whether your flower head is truly “campanulate” or “cylindro-campanulate” and whether your plant of interest, invariably featuring a wide spectrum of leaf widths along a developmental gradient, in fact has leaves that are “narrowly lanceolate” or merely “lanceolate”.

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Northeast of where?

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True of Asteraceae as a whole in the Flora of North America, unfortunately.

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“The Northeast” in this context means northeastern United States.

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Yes sorry Northeastern North America

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Yes the Newcomb’s guide is out of date as well. The paintbrush stroke that is life on this planet how I see it, seems to go double for Asteraceae.

I get all fired up to go out and lock down some species but in the end I always feel a bit lost and uncertain no matter how many photos I take. The variety within a species amongst individuals is both incredibly frustrating and the beauty of the evolution.

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