Eriogonum ID?

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Lori S.
Title: Moderator
Joined: 2009-10-27
Eriogonum ID?

From all the recent discussion about buckwheats, I know I've come to the right place to ask this question! :)

I have been puzzled for some time now about the ID of the Eriogonum that I see in the mountains here. I have thought that they are E. ovalifolium but... are they?

Given its provenance (common on a particular dry, windswept, alpine-zone ridge, and less common in the alpine zone elsewhere in more snow-prone/wetter areas where we hike), it seems to be either Eriogonum ovalifolium or E. androsaceum. (E. umbellatum also occurs in the area at slightly lower elevations, but I think I recognize that one. I know E. flavum reasonably well from the prairies and, while it can occur up into the alpine zone, I have never noticed it there.)

My local reference is Flora of Alberta by Moss and Packer. According to it, E. ovalifolium is found here on "dry plains and rocky outcrops to alpine elevations", while E. androsaceum is found on "rock slides and exposed summits at high altitudes"... so I don't perceive any absolute delineation of habitat from that.

The distribution maps show E. androsaceum present over a wider area along the western mountain border of Alberta, from the Athabasca River headwaters to the U.S. border. E. ovalifolium is also present only along the western mountain border of the province, but is much less widespread. It's present in a region around the North and South Saskatchewan River headwaters, and in another region around the Bow River headwaters and south to the U.S. border. So, both happen to occur in the areas where we hike.

E. androsaceum is described as: "Small plant, often forming dense mats; caudex tufted, scapes 2-10cm high, leaves oblanceolate to spatulate, 1-2 cm long, densely villose or becoming glabrate and green on the upper surface; involucres in a small umbel, sometimes reduced to as few as one; flowers sparingly pubescent" (Flora of Alberta, Moss and Packer, pg. 224).

E. ovalifolium is described as: "Low plant with short, closely branched caudex, thickly set with leaves and densely white-tomentose; leaves oval, orbicular or obovate, about 1cm long; scapes 5-15cm tall; involucres small, cup-like, usually clustered in a single close head; bracts very small, united at base; flowers white, 4mm long, the outer sepals oval to orbicular, the inner ones narrow, spatulate; in our area var. ovalifolium" (Flora of Alberta, Moss and Packer, pg. 224).

The key distinguishes them as follows: E. androsaceum - "flowers attentuate, with a stipe-like base"
E. ovalifolium - "flowers not attentuate, lacking a stipe-like base"; (Flora of Alberta, Moss and Packer, pg. 223).

Looking closely at some of my photos, I thought I could see a stipe-like base. Some flowers seemed to be attenuate (tapering to a narrow base), some not.

To confuse me further:
1) Flora of North America says that the variety that occurs here is depressum, rather than ovalifolium which it says has a yellow perianth. (I've only seen very pale yellow to cream to pink and peachy on the plants in question.)

http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250060170
http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250060437
http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250060439

2) EFlora of British Columbia shows drawings for both E. androsaceum and E. ovalifolium, and both appear to have a stipe-like base in the drawings. One of the photos for E. ovalifolium is from this area (Bragg Ck., AB) and is a match for my plants. There are no photos for E. androsaceum.
http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Eriogonum%20androsaceum
http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Eriogonum%20ovalifoli...

3) In the eriogonum reference below (which was being discussed in another thread: http://nargs.org/smf/index.php?topic=486.msg5001#msg5001 ), E. ovalifolium var. ovalifolium is also described as having yellow flowers (which I take to mean a strong yellow rather than a very pale yellow) but E. androsaceum is described as having pale yellow flowers.
http://www.plantsystematics.org/reveal/pbio/eriog/eriogarden.html

So, here are some photos... I am now leaning towards E. ovalifolium var. depressum, assuming the Moss/Packer reference was wrong about var. ovalifolium being the one that occurs here. Can anyone confirm the ID of these plants?

1-5) Eriogonum ovalifolium var. depressum?

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

I like to make side-by-side visuals, helps to arrive at conclusions, so here are the two drawings put together; E. androsaceum and E. ovalifolium var. nivale.  Of course, you believe you might be seeing E. ovalifolium var. depressum, I'm not sure how it varies from the depicted var. nivale.

There are some aspects a bit different.  The involucre in E. androsaceum is more narrowly campanulate (cone-shaped) and without any sharp teeth at the apex, whereas in E. ovalifolium var. nivale the involucre is more openly campanulate and with 5 pointed teeth... that seems a real characteristic, involucre shape playing a key role in Eriogonum identification.

Regarding leaves, in E. androsaceum the leaves have the margins rolled under rendering a much narrower look to the leaves, whereas in E. ovalifolium var. nivale the basal leaves are "roundish", and without the margins rolled under have a more rounded or spoon-shaped leaf look.

You are correct, these detailed drawings both show stipes, so that is probably an unreliable characteristic.  By the way, I'll be sending James Reveal links to Cohan's mystery Eriogonum in Alberta.  You mentioned "E. umbellatum also occurs in the area at slightly lower elevations, but I think I recognize that one"... I'm not sure I always would, there are 41 varieties in Flora of North America, that must be an all time record for any plant species!

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

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

Thanks for digging into the details, Mark.
Eriogonum ovalifolium var. nivale occurs in BC, apparently, but not in Alberta, according to Eflora of NA.  Eflora of NA says that the only E. ovalifolium occurring in Alberta is var. depressum.  Unfortunately, the eFlora of NA description of var. depressum does not have a lot of detail about the involucre, to allow a comparison between it and var. nivale, or between var. depressum and E. androsaceum.  There seems to be quite a lot of variability in leaf shape even within a variety, viz. Moss/Packer's description of leaf shape for E. ovalifolium.

Interestingly, USDA Plants agrees with Flora of Alberta (that we have only var. ovalifolium), and not with Eflora of NA (which says we have only var. depressum):
http://plants.usda.gov/java/profile?symbol=EROVO5
http://plants.usda.gov/java/profile?symbol=EROVD

BTW, I am happy to believe it is var. depressum that we have, as it seems the description fits better than var. ovalifolium... (and also that these plants are, therefore, E. ovalifolium var. depressum).

Can anyone at least confirm that this plant is E. ovalifolium, rather than E. androsaceum?

McDonough wrote:

By the way, I'll be sending James Reveal links to Cohan's mystery Eriogonum in Alberta.

Would you mind sending mine as well please?  I have a ton of other photos of this plant, which I'll examine re. the involucre details.  As I've mentioned, I think Cohan's "mystery eriogonum in Alberta" is this plant.

McDonough wrote:

You mentioned "E. umbellatum also occurs in the area at slightly lower elevations, but I think I recognize that one"... I'm not sure I always would, there are 41 varieties in Flora of North America, that must be an all time record for any plant species!

Well, I think I can recognize it here, where we only have var. subalpinum (according to Flora of Alberta), and only in relation to the other eriogonums we have, but maybe I'm fooling myself!  :D

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

Skulski wrote:

Thanks for digging into the details, Mark.
Eriogonum ovalifolium var. nivale occurs in BC, apparently, but not in Alberta, according to Eflora of NA.  Eflora of NA says that the only E. ovalifolium occurring in Alberta is var. depressum.  Unfortunately, the eFlora of NA description of var. depressum does not have a lot of detail about the involucre, to allow a comparison between it and var. nivale, or between var. depressum and E. androsaceum.  There seems to be quite a lot of variability in leaf shape even within a variety, viz. Moss/Packer's description of leaf shape for E. ovalifolium.

Interestingly, USDA Plants agrees with Flora of Alberta (that we have only var. ovalifolium), and not with Eflora of NA (which says we have only var. depressum):
http://plants.usda.gov/java/profile?symbol=EROVO5
http://plants.usda.gov/java/profile?symbol=EROVD

BTW, I am happy to believe it is var. depressum that we have, as it seems the description fits better than var. ovalifolium... (and also that these plants are, therefore, E. ovalifolium var. depressum).

Can anyone at least confirm that this plant is E. ovalifolium, rather than E. androsaceum?

McDonough wrote:

By the way, I'll be sending James Reveal links to Cohan's mystery Eriogonum in Alberta.

Would you mind sending mine as well please?  I have a ton of other photos of this plant, which I'll examine re. the involucre details.  As I've mentioned, I think Cohan's "mystery eriogonum in Alberta" is this plant.

McDonough wrote:

You mentioned "E. umbellatum also occurs in the area at slightly lower elevations, but I think I recognize that one"... I'm not sure I always would, there are 41 varieties in Flora of North America, that must be an all time record for any plant species!

Well, I think I can recognize it here, where we only have var. subalpinum (according to Flora of Alberta), and only in relation to the other eriogonums we have, but maybe I'm fooling myself!  :D

I will defer to Jim but have a few comparisons based on the most recent Eriogonum ID Manual updated June 2010 and only made available to those who attended the inaugural meeting  of the  Eriogonum Society

depressum - Involucre description is '2-4 per cluster, 3-3.5 mm'
flowers 4-5mm; perianth white to rose. flowering june-august.......900-3500 m....

androsaceum - Involucre description is '1 per node, narrowly turbinate to turbinate-campanulate, 3-5 x 3-4.5 mm; filaments pilose proximately'
flowers (3.5)4-5(-6.5)mm, including 0.1-0.2 mm stipelike base; perianth pale yellow sparsely pubescent abaxially; tepals monomorphic, narrowly oblong; stamens exserted, 4-5mm; filaments pilose proximately.  Achenes light brown
flowering july-august...... 1700-2700 m.

and so forth....  have fun with this.  Signing off for now...

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

Weiser
Title: Member
Joined: 2009-12-04

According to the manual mentioned by Hugh the Eriogonum flavum varieties found in Alberta are E. flavum v. flavum and  v. piperi.
The Eriogonum ovalifolium varieties are E. ovalifolium v. purpureum and v. depressum
Eriogonum androsaceum also is found in Alberta.

I have taken a few general information excerpts from the manual that we can compare to the photos.

Both the ovalifolium varieties have "Infloresences capitate branches absent"
E. androsaceum has "Infloresences subcapitate or umbellate,...."

E. ovalifolium v. purpureum  "Scapes erect tomentose"
E. ovalifolium v. depressum "Scapes often suberect to decumbent, thinly floccose"
E. androsaceum "Stems ..... aerial flowering stems ascending to erect, slender,
.....tomentose to floccose or subglabrous."

E. ovalifolium v. purpureum "Leaf blades spatulate, oblong, or obovate to oval, tomentose to floccose, margins rarely brownish."
E. ovalifolium v. depressum "Leaf blades elliptic, or infrequently oblong to spatulate, tomentose to floccose, margins not brownish."
E. androsaceum "Leaves basal, occasionally in rosettes...,tomentose: blade narrowly elliptic, densely white-lanate or grayish-tomentose abaxially, floccose and green adaxially, margins entire, usually slighty revolute."

E. ovalifolium v. purpureum "Flowers perianth white to rose or purple"
E. ovalifolium v. depressum "Flowers perianth white to rose"
E. androsaceum "Flowers ...perianth pale yellow....stamens exerted..."

I would put this under E. ovalifolium v. depressum

I will be very interested in Dr. Reveal's assessment.

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

Thanks John, useful to have further compilation of characteristics to tell E. androsaceum apart from ovalifolium.

I wrote to Dr. James L. Reveal, Ph.D, Professor Emeritus, University of Maryland and noted authority on the genus Eriogonum, 1) regarding the mystery Eriogonum from west central Alberta that SRGC member Cohan Fulford posted here:
http://www.srgc.org.uk/smf/index.php?topic=5641.msg170030#msg170030

...and 2) asked him to take a look at Lori's Eriogonum pics here which she believes come closest to E. ovalifolium var. depressum.

Here are his answers:

1) "All images [in Cohan Fulford's link] are of Eriogonum androsaceum  Benth. As for a distinction between E. ovalifolium and E. androsaceum all one needs to do is look at the base of the flower. In the first the rounded base of the flower is directly attached onto the pedicel; in E. androsaceum there is a short stalk ("stipe") that extends from the narrow base of the flower down to the pedicel.

Nice pictures of E. androsaceum and if you look at the narrow leaf blades that are faintly lined on the thinly and darkish tomentose upper surface that will quickly distinguish this species from the broader leaved E. ovalifolium  that is usually distinctly densely white tomentose on a smooth upper surface. The line business is something you can best see in the field as this is faint and does not really preserve on herbarium specimens. The line business is something you can best see in the field as this is faint and does not really preserve on herbarium specimens."

2) Eriogonum ovalifolium var. depressum Blank. is in Alberta, but I have seen no specimens I could assign to var. nivale that far east.

He added: "Be glad to address any questions you might have on Eriogonum"  :D

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

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

Just to add to the fun, here's a photo from Calflora of Eriogonum ovalifolium var. ovalifolium that appears to show stipes (though apparently it should not) and exerted stamens.  Is it misidentified, or am I misinterpreting the term "stipe", or... ?

http://calphotos.berkeley.edu/cgi/img_query?enlarge=0000+0000+0710+2217

Correction:  It's been established that stipes are (probably) not visible in this photo.  What I had interpreted as "stipes" are actually the pedicels.

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:

Just to add to the fun, here's a photo from Calflora of Eriogonum ovalifolium var. ovalifolium that appears to show stipes (though apparently it should not) and exerted stamens.  Is it misidentified, or am I misinterpreting the term "stipe", or... ?

http://calphotos.berkeley.edu/cgi/img_query?enlarge=0000+0000+0710+2217

Word of caution, watch out for the Calphotos site.  I love it, it's a great resource, but since many (most) photos are user donated, there are often misidentifications.  In the genus Allium, I have spotted some fairly obvious (to me) misidentifications among the pool of photos that Calphotos dishes up, so be cautious using this resource on a genus as polymorphous and taxonimically difficult as Eriogonum.

However, aware of the apparent contradiction in the E-Flora of BC line drawings that show both E. androsaceum and E. ovalifolium var. nivale having flowers with stipes, I have already written back to Dr. Reveal about this detail.  See response below from Dr. Reveal.

But aren't we happy about the more established fact, that what Cohan showed us is E. androsaceum, as was suspected?

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:

But aren't we happy about the more established fact, that what Cohan showed us is E. androsaceum, as was suspected?

I am satisfied having had time to reread this topic from start to finish - John supplied more of the detail from the ID manual and Jim's answer fills in from an informed perspective.  Now I want to see this beauty! 
I absolutely agree with Mark regarding the Calflora photos.  Gary Monroe, one of the contributors to Calflora, on the other hand, is usually spot on

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

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

Hi folks, I heard back quickly from Dr. Reveal, and he offers up a good lesson in the anatomy of an Eriogonum flower head (wish I had some fresh flowers to better understand the finer points), but after going through his examples, I think I'm starting to see the difference.

Dr. Reveal's response:
"Jeanne's image of Eriogonum ovalifolium var. nivale is correct; she is showing the flower attached directly onto the pedicel. Look at the following image of E. nervulosum: http://www.plantsystematics.org/reveal/pbio/digitalimages/004867.html
On the left side of the involucre you will see a small number of truncated pedicels denoting where the flowers were attached. You will see (at 12 o'clock) a single flower with a short stipe attached to a pedicel. The stipe is better seen on the flower (at 7 o'clock) that is slightly out of focus and on the ground. In this image of E. umbellatum var. subaridum, a species with a well-defined stipe (http://www.plantsystematics.org/reveal/pbio/digitalimages/002405.html) you can see the long stipe of the flower that is attached to the pedicel, the joint between the stipe and pedicel denoted by a dark line (see the flower on the right at 3 o'clock). (MMcD - pay particular attention to this last example, look for that dark line where one can see the juncture between a "stipe-like" attenuate base of the floret and the short connected stipe; for me, I believe I've been misinterpreting what the "stipe" actually is.)

In an image of old flowers of var. depressum (http://www.plantsystematics.org/reveal/pbio/digitalimages/003188.html) you can see the pedicels much better defined. In this image of Eriogonum ovalifolium var. williamsiae you can see how these flowers are attached onto the pedicel (http://www.plantsystematics.org/reveal/pbio/digitalimages/006883.html).

Hope this is helpful.

The next meeting of the Eriogonum Society will be near Bishop, California, next August."

Edited by L. Skulski to make the first link functional.

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

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

McDonough wrote:

I wrote to Dr. James L. Reveal, Ph.D, Professor Emeritus, University of Maryland and noted authority on the genus Eriogonum, 1) regarding the mystery Eriogonum from west central Alberta that SRGC member Cohan Fulford posted here:
http://www.srgc.org.uk/smf/index.php?topic=5641.msg170030#msg170030

...and 2) asked him to take a look at Lori's Eriogonum pics here which she believes come closest to E. ovalifolium var. depressum.

Here are his answers:

1) "All images [in Cohan Fulford's link] are of Eriogonum androsaceum  Benth. As for a distinction between E. ovalifolium and E. androsaceum all one needs to do is look at the base of the flower. In the first the rounded base of the flower is directly attached onto the pedicel; in E. androsaceum there is a short stalk ("stipe") that extends from the narrow base of the flower down to the pedicel.

Nice pictures of E. androsaceum and if you look at the narrow leaf blades that are faintly lined on the thinly and darkish tomentose upper surface that will quickly distinguish this species from the broader leaved E. ovalifolium  that is usually distinctly densely white tomentose on a smooth upper surface. The line business is something you can best see in the field as this is faint and does not really preserve on herbarium specimens. The line business is something you can best see in the field as this is faint and does not really preserve on herbarium specimens."

2) Eriogonum ovalifolium var. depressum Blank. is in Alberta, but I have seen no specimens I could assign to var. nivale that far east.

He added: "Be glad to address any questions you might have on Eriogonum"  :D

Thanks very much for doing this, Mark.

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.

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

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