Hieracium kalmii [Canada Hawkweed]

[Andrea B.]

Blum, A.G. (2017) Hieracium kalmii L. (Asteraceae) Canada Hawkweed. Flowers photographed in ultraviolet and visible light. http://www.ultraviol...anada-hawkweed/

^{Updated 13 July 2017: New sets added.}

 

 

Comment:

H. kalmii is ubiquitous on Mound Desert Island. In UV the flower has a UV-dark central bullseye with diffuse edges against UV-bright rays - except for a tiny bit of the ray tips which are UV-dark. The curled stigmas are UV-dark. The abaxial surface of the rays shows UV-dark striping, UV-dark sepals and a few UV-dark trichomes. There is also a nice blue and yellow false color combination for the abaxial side of the capitulum.

 

Reference:

1. Mittelhauser et al. (2010) Kalm's Hawkweed, page 94. The Plants of Acadia National Park. The U. of Maine Press, Orono, ME.

2. New England Wild Flower Society (2013) Hieracium kalmii. Canada Hawkweed. https://gobotany.new...eracium/kalmii/

 

Synonyms:

• Kalm's Hawkweed
  
• Hieracium canadense Michx.
  
• Hieracium canadense Michx. var. fasciculatum (Pursh) Fern.
  
• Hieracium canadense Michx. var. kalmii (L.) Scoggin, an illegitimate name
  
• Hieracium kalmii var. fasciculatum (L.) Lepage
  
• Hieracium umbellatum var. canadense (Michx.) Breitung
  

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SET 1

Southwest Harbor, Maine, USA

11 July 2012

Wildflower

 

Equipment [Nikon D300-broadband + Carl Zeiss 60mm f/4.0 UV-Planar]

 

Click photos for a larger view.

 

Visible Light [f/11 for 1/3" @ ISO 200 with onboard Flash and Baader UVIR-Block Filter]

 

Ultraviolet Light [f/11 for 1/60" @ ISO XXX with SB-14 UV-modified Flash and Baader UV-Pass Filter]

 

Ultraviolet Light [f/11 for 1/60" @ ISO XXX with SB-14 UV-modified Flash and Baader UV-Pass Filter]

Abaxial view.

 

 

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SET 2

Southwest Harbor, Maine, USA

08 August 2014

Wildflower

 

Equipment [Nikon D600-broadband + Carl Zeiss 60mm f/4.0 UV-Planar]

 

Click photos for a larger view.

 

Visible Light [f/11 for 1/3" @ ISO-400 with onboard Flash and Baader UVIR-Block Filter]

Hieracium close up in the afternoon! This flower was beginning the process.

 

Ultraviolet Light [f/11 for 15" @ ISO-400 with SB-14 UV-modified Flash and Baader UV-Pass Filter]

 

Ultraviolet Light [f/11 for 15" @ ISO-400 with SB-14 UV-modified Flash and Baader UV-Pass Filter]

Abaxial view. Flower stem is bending out of its container.

 

 

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SET 3

Southwest Harbor, Maine, USA

08 August 2014

Wildflower

 

Equipment [Nikon D600-broadband + Carl Zeiss 60mm f/4.0 UV-Planar]

 

Click photos for a larger view.

 

 

 

 

 

[igoriginal]

I REALLY like the underside shot. Wow.

 

Definitely expands my thinking / awareness, in terms of how / where flower UV signatures manifest themselves, and hence where they can be located (and not just a "top-view" phenomenon, exclusively.)

 

I also noticed the additional UV-absorptive signatures along the very tips of the petals on the underside, which are not a contiguous part of the centralized UV-absorptive pattern, at top and center. Another illuminating realization for me!

 

Thank you.

[colinbm]

What a fascinating flower Andrea & so well presented :)

Col

[nfoto]

I see from the nomenclature details this is a relative of H. umbellatum, so presumably it has the sexual reproduction behaviour of the latter species as well? Their UV signatures seem to have much in common. I must reshoot H. umbellatum later this year when it enters its blooming stage (a mid July to August flowering species in my country).

 

Technically a well-tempered presentation, but the sharpening does bring forth the weave of the background too. No bearing on the documentary value of course, just a little nitpicking from a photographer's perspective.

[Andrea B.]

Thanks all.

 

Yes, backgrounds are difficult. I never know what to use. I suppose the ideal thing would be some kind of "photographer's cloth". In the case of this Hieracium I was using a big book with a cloth cover.

[nfoto]

You really need a cover or fabric without a defined texture. Black flock wool is near ideal.

[Andrea B.]

I don't think I know what "black flock wool" actually is ?

Is this a cloth which can be purchased at a photo supply store ?

[colinbm]

Perhaps a fabric shop, or get a black flock wool dress & cut it up :)

It doesn't have to come from a flock of black sheep, just one will do..........

Col

[nfoto]

The same stuff you see used in light baffles of lenses ....

[JCDowdy]

I don't think I know what "black flock wool" actually is ?

 

Flocking material:

http://www.fpi-protostar.com/flock.htm

http://www.scopestuff.com/ss_flok.htm

http://www.edmundoptics.com/lab-production/general-tools/light-absorbing-black-out-material/1502

 

Or just do like I do and go to the fabric store and get a couple of square yards of black felt. :)

[Andrea B.]

Second and third set added.

[OlDoinyo]

The shape of the ray petals reminds me of chicory--I guess that they are related.

[Andrea B.]

Cousins, you could say. :D Both Chicory and Hawkweed are members of the Asteraceae family.

[OlDoinyo]

Both Chicory and Hawkweed are members of the Asteraceae family.

 

And both have pentadentate ligules. Do they both belong to Cichorieae, perhaps?

[nfoto]

Yes, they do. The subfamily with only ligulate flowers.