Keying the Clarkia -- and late GBBD for July



Keying the Clarkia

I have not been sure what kind of Clarkia it is that grows locally, and which I have propagated for garden use. Town Mouse thought maybe C. purpurea, and Claire of nearby Curbstone Valley thought C. rubicunda.

So, I got out my hardbound copy of The Jepson Manual to let my fingers do the leg work. I was amazed and delighted that it took a lot less time than I thought - maybe 15 minutes - not bad for a rank amateur. However today I realize, my Clarkia has one key attribute of C. purpurea:
sepals staying fused in 2's or all coming free.
You can see the sepals staying fused in 2s in the opening picture. Here is another picture that might be helpful - showing an immature fruit, and a kind of bashed flower, with some petals removed:


3 hours later... I'm still not sure... Dang!

As you may know, with a dichotomous key, you identify a plant by making a series of binary (dichotomous) choices - it's always one thing or another. You jump to the choice that matches the plant you're trying to ID, then again within that section, choose one thing or another, always based on some observable trait. Which works if you can clearly observe the trait!

These keys don't come out of nowhere. Someone has to write them. In this case, the someone was Harlan Lewis, who died in 2008, just short of his 90th birthday. He is closely associated with the Clarkia genus, and he worked on this with his wife Margaret at UCLA. I find it interesting to know about the California botanists and the history of botany in this state, and maybe you do too. You can read an In Memoriam article about Professor Lewis and his work here.

So - here's how it went on my first go. Options I chose are shown in bold (I provide a mini key to the terms after the entry).

1. Fr 2-3 mm, nut-like, indehiscent, 1-2 seeded
1' Fr > 5 mm, not nut-like, dehiscent, many-seeded

2. Petal blade lobed above
2' Petal blade not or inconspicuously lobed above

11. Petal claw 2-lobed or -toothed, not entire
11' Petal claw +/-0 or entire

20. Infl axis in bud recurved at tip, in fl +/- straight; buds pendent
20' Infl axis in bud gen +/- straight; buds erect or reflexed

35. Fl buds reflexed
35' Fl buds erect

43. Ovary, immature fr 4-grooved
43' ovary, immature fr 8-grooved

The ovary grooves would be different if it was C. purpurea: the ovary would have to be 8-grooved. But the example I found looks like 4 grooved to me!

44. Petals with a +/- red spot or zone at base
44' petals with a red spot or marks near middle

45. Petals 10-13 mm; stigma beyond anthers ; Clarkia rubicunda!
45' Petals 5-13 mm; stigma not beyond anthers

and here's the entry:
C. rubicunda (Lindley) Harlan Lewis & M. Lewis. ST: decumbent to erect, < 1.5 m, puberulent. LF: petiole < 1 cm; blade 1–4 cm, lanceolate to elliptic. INFL: open or dense; axis in bud straight; buds erect. FL: hypanthium 4–10 mm; sepals staying fused in 4s; corolla bowl-shaped, petals 10–30 mm, obovate to fan-shaped, rosy-pink to lavender, ± red spot or zone at base; stamens 8, anthers alike; ovary 4-grooved, cylindric, stigma exserted beyond anthers. n=7. Openings in woodland, forest, chaparral near coast; < 500 m. CCo, SnFrB.
(Here's a link to Clarkia Rubicunda in Jepson on line.)

BUT: "sepals staying fused in 4s" - mine are separated or in pairs!


For Purpurea the trail goes like this, starting from the point where the trail diverges:

43. Ovary, immature fr 4-grooved
43' ovary, immature fr 8-grooved
(I have to take this on trust - mine do NOT look 8-grooved.!)

47. Stigma not beyond anthers; petals gen 5-15 mm
47' Stigma gen beyond anthers; petals 10-60 mm

51. Ovary, immature fr fusiform, grooves 8, 4 deeper (C. amoena ssp. whitneyi)
51' Ovary, immature fr gen +/- cylindric, grooves 8, equal (??)

52. Petals +/- without a red or purple spot
52' Petals gen with a red or purple spot

53. Petals dark reddish purple [oh-oh - I'm in trouble! color differentiation...!]
53' Petals pink or lavender to purple or purplish red, below often cream or lighter

55. Infl open; If linear to narrow -lanceolate -- C. speciosa ssp. immaculata [not native here]
55' Infl dense; If wide-lanceolate to elliptic or ovate -- C. purpurea ssp. purpurea

Unfortunately I don't know what "Infl open" and "Infl dense" mean, visually. But C. immaculata doesn't grow around here - so I can ignore that choice right off!

All I can say right now is that if it's C. rubicunda, then how come the sepals are separate or in pairs instead of fused?

But if it's C. purpurea, how come the ovary seems to have 4 grooves instead of 8?

Or am I looking for the ovary in all the wrong places? Sigh. My only conclusion is: I need a teacher!

Glossary of Terms

For those interested in knowing the meaning of the botanical terms used in the key or the entry, here's a list or most of them, using the glossary found in Jepson:
  • dehiscent: Splitting open at maturity to relese contents. Said especially of fruit or anthers.
  • claw: Stalk-like base of some free sepals or petals
  • reflexed: Abruptly bent or curved downward
  • stigma: The part of a pistil on which pollen is normally depositied, generally terminal and elevated above the ovary on a style, generally sticky or hairy, sometimes lobed.
  • pistil: Female reproductive structure of a flower (there's a lot more but that's enough!)
  • style: Stalk-like portion that connects ovary to stigma in many pistils.
  • anther: Pollen forming portion of a stamen.
  • stamen: Male reproductive structure of a flower (there's a lot more but that's enough!)
  • puberulent: having hairs visible only when magnified.
  • hypanthium: Structure derived from the fused lower portions of sepals, petals, and stamens and from which these parts seem to arise, the whole generally in the shape of a tube, cup, or plate.
  • sepals: Individual member of the calyx, whether fused or not, generally green.
  • calyx: Collective term for sepals; outermost or lowermost whorl of flower parts, generally green, and enclosing remainder of flower in bud.
  • corolla: Collective term for petals; whorl of flower parts immediately inside or above calyx, often large and brightly colored.
  • obovate: egg-shaped, widest above the middle. (Not given - you have to figure this one out. ob- means "inversion of shape - e.g., lanceolate and oblanceolate leaf blades are widest below and above the middle, respectively." Therefore I deduce the definition I gave from ovate, "egg-shaped in two dimensions, widest below the middle."
Jepson uses lots of abbreviations, for example:
ST: stem
LF: leaf
INFL: inflorescence
FL: flower
FR: fruit
The book is already huge, so I can understand their need for economy. But it does force you to learn their codes. Practice makes this easy I'm sure. I should make myself do one keying exercise a week! Next one will be the mystery lupine!


One subsection tells you where the plant grows. In the case of C. Rubicunda, for example, it's not so widely spread:
CCo, SnFrB.
  • CCo is Central Coast
  • SnFrB is San Francisco Bay Area

Horticultural Information in Jepson
Maybe of most interest to gardeners is the very useful, if compressed, horticultural information section in Jepson, which is preceded by a tiny flower icon. For C. rubicunda it contains the following:
SUN,DRYorIRR:7-9, 14-17, 22-24; CVS
Jepson's guide to the abbreviations tells you the following:
  • SUN: Does best in +- full sun
  • DRY: Intolerant of frequent summer water
  • IRR: Requires moderate summer watering (irrigation)
  • CVS: Cultivars are available in the trade.
The numbers refer to Western Garden Book zones. Zones that are especially appropriate are indicated by bold-face numbers.
  • 7-9: Great valley and Surrounding Low Mountains
  • 14: Ocean-influenced northern and Central California
  • 15-17: Coastal Climates of Northern and Central California [this is me! - Zone 16]
  • 22-24: Coastal Climates of Southwestern California.
So that is our schoolwork over, not entirely satisfactorily, and our understanding suitably enriched and confused.

One thing it does not talk about is deer, and whatever this Clarkia is, I've found the deer quite like nibbling the flowers, unfortunately.

Now we get to look at some pictures of flowers in my garden this month and rest our brains!

GBBD Pictures

Mostly for my benefit, so I can look at the blooms year-over-year, I'm putting a bunch of pics below. Forgive me for not annotating them. I'm anxious to get out in the garden and finish planting Hummingbird Hill! If you want to know about any, leave a comment and I'll give the info in response.























Comments

Country Mouse said…
This was a post that got complicated. FWIW, Jeffrey Caldwell inclines towards rubicunda which is more common hereabouts, and notes that Clarkias do hybridize.
That's good to know Jeffrey's take, my next question was going to be could this be an intergrade species. Rubicunda seemed plausible for this area, but from your photo it didn't quite look like a perfect specimen. Maybe do an experiment in the greenhouse? Save some seed, propagate the seeds, and see what blooms? If it's a hybrid, the resulting plants likely won't all come true to the parent...as if you don't have enough to do! LOL. ;)
Joe said…
I love that lupine bush. I'm rather new to California native plants, what species is it? thanks.
Country Mouse said…
I'm loving the lupine too, Joe. I'm not sure - it's my next keying exercise. One advisor's theory is that it's the lavender version of Lupinus arboreus, which is normally yellow and grows on the coast nearby - and which can be invasive out of its native locale.

Clare - I sure will be growing from seed. I'm a bit concerned that I let two other CNPS-bought clarkias bloom though - C. lewisii and C. unguiculata. They are so pretty - what's a gardener to do! Am I going to have to expunge them and start over with my native clarkia breeding program?
Sue Langley said…
I have had a heck of a time identifying my clarkias. We have a very tall one, three feet tall with many branches and a shorter more slender version. As far as I know from sight, looking on Calphotos, they are Four-spot and Speckled fairyfans.
I so admire your understanding of Jepson's! At first, it looks all Greek, but after reading the glossary and key to abbreviations, is was more understandable. I have a LOT to learn.
Country Mouse said…
Hey Sue - it sure is painful getting the hang of Jepson, but I have benefited from the effort. When I saw Toni Corelli and her husband Richard keying out plants in the field - I was so inspired - they whipped out an ID in no time flat! Years of practice pay off I guess :-) Regarding your clarkia ID issues - Jeffrey Caldwell, local naturalist, said that clarkias do hybridize - and that may well be the issue - nothing is as simple as the books make out. Even big complicated books like Jepson!