Zone 8 north central Fl. Growing in partial to heavy shade. Sorry about the bloom photo but the day was so very windy I had trouble holding it still even long enough for the camera & the camera is quick. The blooms didn't open until about 10:30 - 11:00.

Looks like Lactuca. Possibly Lactuca floridana.

The leaves don't match Lactuca floridana Jay ..

http://www.alabamaplants.com/B...

It looks like a type of Asteraceae, look at Symphyotrichum subulatum which is similar but not the one.

http://www.wnmu.edu/academic/n...

The leaves should be easily recognised if anyone knows it but so far I'm drawing a blank.

I was concerned with the leaves also. That & the fact that none of the photos or text mentioned the reddish - purplish tint. The buds would show the hue but not the leaves. I found this though:

http://www.illinoiswildflowers...

Part of the text being --- "The central stem is terete and glabrous, light green or reddish green (sometimes with purple streaks), and often glaucous. The alternate leaves are light green to dark green, sometimes with purple edges or a yellowish cast." "The largest leaves have deep pinnate lobes, while the smaller leaves have shallow pinnate lobes or none; they are wider at their bases than at their tips, and their bases clasp the stem."

Also see:

http://www.cas.vanderbilt.edu/...

http://pick4.pick.uga.edu/mp/2...

http://minnesotaseasons.com/Pl...

I think it's L. canadensis aka Florida blue lettuce among others.

The leaves on L. canadensis only resemble your plant in a similarity in form, other than that they are very different.

Okay, here we go for another try at this one with some better photos of the bloom. I counted petals or rays & there are around 20. The rays are not pointed or rounded at the ends but rather blunt as if cut by scissors. This plant has pure white thick latex like sap when you break the stem. And when you even barely touch the buds your fingers come away sticky even though you can see no sap on the buds or your fingers. I think Janet is on the right track or at least that this is not wild lettuce. It must be in the aster family. They are all over our property so they can't be that rare?????

Okay, positive ID. This is Lactuca floridana & Jay called it.
See:

http://www.toledo-bend.us/inde...

That's really strange Ann, the leaves on the photos on your link do look to match but look at the leaves on this site ...

http://www.alabamaplants.com/B...

And ..

http://www.cas.vanderbilt.edu/...

http://www.delawarewildflowers...

I think the site you linked to has got it wrong.

I know Janet but there are multiple references to the Lactuca having highly variable leaf appearance but there is only one with the purple flowers & that is the L. floridana.

flaflwrgrl said:I know Janet but there are multiple references to the Lactuca having highly variable leaf appearance but there is only one with the purple flowers & that is the L. floridana.

But, you are assuming it is Lactuca, which it probably is not. Yes, leaves are often variable as shown is the examples Iinked to, but I doubt very much they are that variable.

Lactuca graminifolia

http://www.shirleydenton.com/p...

http://eol.org/pages/467166/en...

http://plants.usda.gov/java/pr...

http://lyvon.smugmug.com/Rober...

You surely did it Janet!
I've been hunting & hunting these many hours & got an idea it was the L. graminifolia but all the photos showed only straight leaves.
No doubt in my mind you are exactly correct!
Thank you!

If I had checked out all the Lactuca species in the first place I might have got there quicker! The leaves were so different to L. floridana I had doubts about it being Lactuca.

And on the opposite end of the spectrum, I was so sure it was Lactuca. I had the advantage of intimate knowledge of the plant in person & everything except the leaves was so right on for L. floridana. But you see I even had my doubts at one point there.
I'm just glad it's over!