Those White American Asters - is it Calico or Bushy or Ontario or Hairy or just plain Small?

I wish I had the answers! Small white Symphyotrichum species. Here's maybe some of what I know.

For the observer/photographer: see this post.

Remember the leaves. Remember the backs of the leaves. Oh please, friends, please remember the leaves. Won't you please think of the backs of the leaves?

Remember the involucres. Those are the backs of the flower heads and are made up of the phyllaries. Phyllaries look like little green fish scales. The involucres hold the flower together. And they with phyllaries are one of the main ways, or perhaps the main way, you (and the identifier) can tell which species it is (besides the leaves... did I mention the backs of the leaves?). If you could only take one photo of an Astereae species, it should be of the back of the flower head showing those phyllaries.

Get close and focused enough (coming from someone whose hands shake) for a good look at the disks. That's the middle part of the flower head (you knew that). Those and the involucres and backs of the leaves tell so much in this genus, the entire tribe actually.

If the computer imaging says it's Symphyotrichum lateriflorum, it probably is, but (no data here) it could also be one of those other (ten thousand) white Astereae (in other genera as well) that have disks that turn from cream or yellow to pink or magenta. For white asters, what I've seen is that the first suggestion by iNat is the genus. A species is nearly always the second suggestion. Identification to genus isn't a bad thing, and without phyllaries and leaves, it may be the best that can be done.

I know that the Description section of the Wikipedia article for Symphyotrichum lateriflorum is pretty comprehensive, with photos. I know that the Description section of the Wikipedia article for Symphyotrichum ontarionis is not as comprehensive (yet), but does have at least some information to help with ID, and has a few good pictures that can help.

I know that it is quite difficult to find information on (and observations of!) Symphyotrichum racemosum, but it has a lot of tiny leaves (don't use that as your sole ID criteria, I just like them). I know that Symphyotrichum dumosum has lots and lots of bracts. And they're pretty cool.

I know that iNat says that the most common misidentification with S. lateriflorum (calico aster) is S. cordifolium, common blue wood aster, which I think is odd (not because it's wrong, but because they are actually very different but can look somewhat alike in photographs).

I know that if your disk florets are open with protruding stamens but are not spreading, and your disks have multiple colors (yellow, pink, magenta), then it's likely not calico aster (Symphyotrichum lateriflorum) even though the computer ID will probably say it is. It's likely S. urophyllum, S. drummondii, S. cordifolium, or some such thing. You know what would help there? Leaves. Did I mention leaves? Did I mention the backs of the leaves? Phyllaries.

What else? Oh, so much more that I'm sure people much smarter than me could add in the comments.

The biggest thing is that white asters are hard. But (in my opinion) they are also the best. They are a challenge, and if you live in an area where there are many species of white Astereae (regardless of the genus), you have quite the opportunity to learn and teach us! I know it's January. And I know they won't be blooming until late July at the earliest, but there are thousands of observations to view, and maybe a few of them could use IDs.

Oh, and dang, I miss summer.

Thanks for reading this gibberish.

Posted on 24 de janeiro de 2021, 10:50 AM by elizabeth1067