Helianthus ID

[Austrinum]

Anybody out there good with Helianthus ID?  I found a sunflower at Sprewell Bluff Natural Area (Pine Mountain, near the Flint River) that doesn't want to key out easily.  When I run it through Weakley it keys out to Helianthus smithii.  The only image I can find of H. smithii is a Univ. of Tennessee herbarium specimen and it doesn't look much like what I found. 

In Weakley (page 168 of 11 Jan 2007 edition), I used Key D (perennial with leafy stems and yellow disk flowers).  The stems are glabrous.  Nearly all the leaves are opposite.  Leaves are sessile, glabrous (or nearly so), dark green, with a single midvein (definitely not tri-nervate).  That takes you to H. smithii.  The habitat description for H. smithii sounds right (dry forests and woodlands), but the geographic location does not (Weakley says N. Georgia mountains). 

When I went back for another look, I noticed that 2 of the 6 or 7 stems had whorled leaves (one node on one stem and two nodes on the other), so I tried going with 'leaves whorled'.  That takes you to H. verticillatus, but it is a sunflower of wet calcareous prairies.  The top of Pine Mountain is anything but.

I am going to try and get some digital pictures in the next few days.  In the meantime, anybody have any suggestions, criticisms, or ideas?

Hal Massie

[Rich]

Hal,

I think H. smithii is probably correct.  It is known from the Talladega National Forest in Alabama and is on the Forest Service Sensitive Plants list for the Shoal Creek Ranger District. David Whetstone (Jacksonville State University Botanist )and I found (Dave identified) a population in the Talladega National Forest earlier this year over by Anniston. The plants exhibited the charateristics you describe.  Particularly the mixture of opposite and whorled leaves (we even had a couple with alternate leaves).  All were H. smithii, though they did not necessarily look like typical H. smithii - we attributed that to the drought.

It is not that far from Pine Mountain over to the Talladega NF, so it may be that Weakley's range is limited by previous collection limitations.

[Austrinum]

Rich,

I made one bad mistake in trying to key this plant.  I did not look closely at the involucral bracts. 
I went back to Sprewell Bluff with Chris Inhulsen in late November and we found this plant still flowering.  He agreed that it looked like a Helianthus, but we couldn't get it to work in any key.  Finally, at home, I looked closely at the bracts and using Cronquist, Weakley, and Radford, determined that it had to be a Coreopsis species.  I still couldn't get it to any particular species...darn thing just won't fit anywhere, but I am confident it is Coreopsis.  The strange thing is that all of the Coreopsis species that come close flower June to September.  This plant was just starting to flower in early October and was still blooming in early December.  That doesn't sound like a self-respecting Coreopsis.  I've attached a photograph of the mystery plant flowerhead in comparison with a Helianthus microcephalus flowerhead.  You can see why we thought this was a Helianthus.  The mystery plant is on the right. 

Hal,

I think H. smithii is probably correct.  It is known from the Talladega National Forest in Alabama and is on the Forest Service Sensitive Plants list for the Shoal Creek Ranger District. David Whetstone (Jacksonville State University Botanist )and I found (Dave identified) a population in the Talladega National Forest earlier this year over by Anniston. The plants exhibited the charateristics you describe.  Particularly the mixture of opposite and whorled leaves (we even had a couple with alternate leaves).  All were H. smithii, though they did not necessarily look like typical H. smithii - we attributed that to the drought.

It is not that far from Pine Mountain over to the Talladega NF, so it may be that Weakley's range is limited by previous collection limitations.

[Austrinum]

I tried to send some pictures of the leaves on this mystery plant, but they exceed the 128 Kb limit.  Sorry.

[Rich]

Bummer, the DYC 's score again.

[Richard]

Hey Hal!

Are you sure the mystery plant is on the right? The plant on the right does look like Helianthus microcephalus (or at least a Helianthus of some kind). I am 99.9% sure the plant on the left is a Bidens, not a Coreopsis. Bidens like Coreopsis has its involucral bracts in two series. In Bidens the outer bracts are usually green and the inner yellow like the rays. This involucre characteristic is what I think led you to Coreopsis. Additionally, Bidens also fits the blooming time you mention, while Coreopsis does not. The habitat seems a little strange thou, Bidens is usually found in wet locations (at least around here). Is there any moisture where these plants are growing? I should have stated at the beginning that I should be slapped for trying to identify a DYC by photograph, ha! ha! Hal, try running it through a Bidens key and see what you come up with. Oh, and that's the last time I'll take the time to put the scientific names in italics, too much trouble!

Richard

[Austrinum]

Hey Hal!

Are you sure the mystery plant is on the right?

Richard,

The mystery plant is indeed on the right.  I have several more pictures if you are interested
in seeing them.  The size restriction on this forum will not allow me to post them here, but I would be
delighted to send them to you at home.

The plant on the right does look like Helianthus microcephalus (or at least a Helianthus of some kind). I am 99.9% sure the plant on the left is a Bidens, not a Coreopsis. Bidens like Coreopsis has its involucral bracts in two series. In Bidens the outer bracts are usually green and the inner yellow like the rays. This involucre characteristic is what I think led you to Coreopsis.

In the mystery plant, the involucral bracts were in two rows, with the lower row wider and spreading.  The upper row (inner row) was upright, almost appressed.  As I recall, both rows were green.

Additionally, Bidens also fits the blooming time you mention, while Coreopsis does not.

The problem with Bidens is that none of the leaves I looked at were serrate, and none were
obviously dissected.  The upper leaves, at least, appear to be simple, glabrous, and entire. 

 The habitat seems a little strange thou, Bidens is usually found in wet locations (at least around here). Is there any moisture where these plants are growing?

That is the other major problem with Bidens...these plants were growing on top of Pine Mountain in an extremely dry, rocky habitat.  The area had been the site of a prescribed burn in February, so it was basically bare mineral soils with some pine straw.  Despite fire and extreme drought, coupled with an already very dry habitat, these plants were flowering as though life just couldn't get any better!

 I should have stated at the beginning that I should be slapped for trying to identify a DYC by photograph, ha! ha! Hal, try running it through a Bidens key and see what you come up with. Oh, and that's the last time I'll take the time to put the scientific names in italics, too much trouble!

I agree, it is a pain to put the plant names in italics.  I did try running the plant through the
Bidens key (only Radford so far, my Weakley is out in the truck and I am far too tired to go out and get it) and it doesn't seem to fit there either.  I'll try Weakley tomorrow, but I don't think this is going to fit under Bidens.  I can't wait to get someone more knowedgeable than myself out to Sprewell Bluff and look at this plant.  It is driving me crazy!

Thanks!

Hal

[Richard]

Ok, my bad. The mystery plant is on the right. Thanks Hal for all the excellent pictures you sent to me, and I believe you are correct that it is a Coreopsis. Judging from all the pictures I've seen so far, I don't see anything that would disqualify it from being Coreopsis major. The lower leaves appear whorled, but are really two opposite leaves that are deeply 3-lobed; large flower; size of plant is right. The only thing I can't account for is the strange blooming time. There was even a variety that had a smooth stem, C. major var. stellata that is not recognized at this time. I think this may be the best I can do without seeing / examining the plant.

Richard