Eriogonum ID?

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Mark McD
Title: Moderator
Joined: 2009-12-14

Skulski wrote:

Cohan's photos include one with a side view of the inflorescense, though I don't find it to be quite close enough or clear enough to definitively see stipes.  Can anyone else confirm the presence of stipes there?   At this point, I guess I'm led to conclude then that the distinction between E. ovalifolium and E. androsaceum can be made primarily on the leaves... ?

Sorry, I'm not following...  in 2) above, was Dr. Reveal commenting on the ID of the plants in my photos (as being Eriogonum ovalifolium var. depressum Blank.??) or was he making a more general comment on the varieties that occur in Alberta, not specifically commenting on my photos?   Thanks in advance for clarifying.

It seems that there is enough foliar differences to make a distinction between the two species, but certainly closely examining the flowers helps too, I think you'd have to look VERY CLOSE at a partially pulled-apart flower head to seed the stipes if present.

By inference I think he's okay with the E. ovalifolium var. depressum ID, that's my take on it.

Let me also share a tangential identification exercise, with the genus Ophiopogon.  I was working with a guy at Plant Delight's Nursery to find a proper ID on what goes around as Ophiopogon chingii (of Hort) but that I felt was actually another species, O. umbraticola. In this exercise, one of the things that came out of it was a feature (perhaps particular to the genus Ophiopogon) referred to as "pedicel articulation", with species descriptions calling out possibilities such as proximal, middle, and distal.  Looking at closeups of the flowers, one can see a flower that narrows to an apparent pedicel, that pedicel connecting and joining to a subtended pedicel (or stipe) off the stem, often the connection at a "broken" angle, making the "pedicel articulation" a bit more apparent.  The situation in Eriogonum seems somewhat analogous.  I attach an image of the flowers of O. umbraticola, that shows that "pedicel articulation".

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

HughGmail
Title: Moderator
Joined: 2009-07-08

McDonough wrote:

Skulski wrote:

Cohan's photos include one with a side view of the inflorescense, though I don't find it to be quite close enough or clear enough to definitively see stipes.  Can anyone else confirm the presence of stipes there?  At this point, I guess I'm led to conclude then that the distinction between E. ovalifolium and E. androsaceum can be made primarily on the leaves... ?

It seems that there is enough foliar differences to make a distinction between the two species, but certainly closely examining the flowers helps too, I think you'd have to look VERY CLOSE at a partially pulled-apart flower head to seed the stipes if present.

Lori/Mark - the image is not clear enough for me to confirm stipe presence.  Regarding id of eriogonum, one of the challenges with had in the classroom session with Dr. Reveal in Reno, was the small size of some of the features in eriogonum.  We were forewarned to be sure to bring at least a 14x lens..  Sometimes the stipe joint was so subtle as to be easily overlooked.  I believe Weiser will confirm my observations.  We did have a few lab microscopes available to us which made identification a bit easier.  I personally carry a 10x. 14x, and 20x lens when in the field - it helps to have the ability to see these smaller features.  We were also advised to bring a dissecting needle or sharp blade for taking apart the flower heads -

For exercises as fun as this one, I have been going back to the subgenera to start identification.  In our example, therefore, I start with E. ovalifolium var. depressum and see that it is in subgenus Eucycla and E. androsaceum is in subgenera Oligogonum.  Although the difference in the leaves is certainly a clue, I find numerous other distinctions in the two subgenera - without a sample to tear apart I believe for me an identification would be more an educated guess than a positive identification - It's good to have Jim so available and willing to share his lifetime of experience at this point.

Hugh Mac Millan
Former NARGS Web Master, Moderator
Eriogonum enthusiast
Zone 5+- - Front Range, Colorado (Denver area)

Hoy
Hoy's picture
Title: Member
Joined: 2009-12-15

You haven't started barcoding the plants yet to confirm the species? This is not a joke, as you may think!
http://en.wikipedia.org/wiki/DNA_barcoding

Trond
Rogaland, Norway - with cool, often rainy summers  (29C max) and mild, often rainy winters (180 cm/year)!

Lori S.
Title: Moderator
Joined: 2009-10-27

I'll be sure to take my bar code reader out with me next time!  ;)

What image is being referred to below?  Is it the drawing at eFlora of BC or ... ?

McDonough wrote:

Dr. Reveal's response:
"Jeanne's image of Eriogonum ovalifolium var. nivale is correct; she is showing the flower attached directly onto the pedicel.

Lori
Calgary, Alberta, Canada - Zone 3
-30 C to +30 C (rarely!); elevation ~1130m; annual precipitation ~40 cm

HughGmail
Title: Moderator
Joined: 2009-07-08

Hoy wrote:

You haven't started barcoding the plants yet to confirm the species? This is not a joke, as you may think!
http://en.wikipedia.org/wiki/DNA_barcoding

Interesting article - a glimpse to the future!  On the other hand, it's nice to see all the folks on this thread running to their references and honing up on their skills!

Hugh Mac Millan
Former NARGS Web Master, Moderator
Eriogonum enthusiast
Zone 5+- - Front Range, Colorado (Denver area)

Weiser
Title: Member
Joined: 2009-12-04

As Hugh pointed out we dissected a lot of flowers in the class peering through loupes and hand lenses. Of course it always helped to have a steady hand and a botanist setting beside you as a reference source. ;)

From the High Desert Steppe
of the Great Basin and the Eastern
Escarpment of the Sierra Nevada Range
Located in Reno/Sparks,NV  zone 6-7
http://www.flickr.com/photos/sierrarainshadow/
John P Weiser

Mark McD
Title: Moderator
Joined: 2009-12-14

Skulski wrote:

What image is being referred to below?  Is it the drawing at eFlora of BC or ... ?

McDonough wrote:

Dr. Reveal's response:
"Jeanne's image of Eriogonum ovalifolium var. nivale is correct; she is showing the flower attached directly onto the pedicel.

He is referring to the drawing in eFlora of BC.

Rewritten (my interpretation of what was the stipe and what was the pedicel was backwards):  In that one photo of E. umbellatum var. subaridum that Dr. Reveal had a URL for, looking into the flower head, viewing the flower on the right at 3 o'clock, you can detect a very subtle line or joint below the flower, and a little bit further down the narrow stipe another slightly darker line indicating the joint with the pedicel.  In another link by Dr. Reveal, one can see pedicels that are left behind after the flowers with their stipes shed.  Since the stipe and pedicel are inline and continuous, it can be hard to discern if a stipe is present; so when when looking at drawings that show a floret, one doesn't really know if one is seeing a stipe, a pedicel, or a stipe-pedicel combination, because it all looks basically the same unless examined very closely.

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

Mark McD
Title: Moderator
Joined: 2009-12-14

Hugh wrote:

I personally carry a 10x. 14x, and 20x lens when in the field - it helps to have the ability to see these smaller features.  We were also advised to bring a dissecting needle or sharp blade for taking apart the flower heads -

I can envision the Eriogonum Posse, Hugh at the head, donning a leather holster with gleaming 10x-20x caliber lenses, dissecting needles, and a bar-coder45, and a bottle of scotch, wrangling wild buckwheat IDs ;D  I'd like to get some of this gear myself and come out for the next Eriogonum meeting in CA.

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

Lori S.
Title: Moderator
Joined: 2009-10-27

Great!  Thanks for the explanation!

MMcD edit:  Photo removed as I had misinterpreted and misled Lori on the stipe and pedicel relationship.  See further in this topic for an annotated photo showing the stipe and pedicel relationship.

Lori
Calgary, Alberta, Canada - Zone 3
-30 C to +30 C (rarely!); elevation ~1130m; annual precipitation ~40 cm

Mark McD
Title: Moderator
Joined: 2009-12-14

Skulski wrote:

Great!  Thanks for the explanation!

So, to check if I understand what has been said, is the annotation that I added to Dr. Reveal's photo (below) correct?

Yes!  I believe so.  No, my interpretation was backwards, so it is the other way around,
see:  http://nargs.org/smf/index.php?topic=493.msg5099#msg5099

Don't you wish that the floras would show a diagnostic photo or drawing for each genus, to helps its users to understand the important criteria for each genus; to help them understand terms used in the keys.

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

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