Hypochaeris radicata [Cat's Ear]: An Australian Version

[colinbm]

Borot-Moloney, Colin (2021) An Australian Version of Hypochaeris radicata L. (Asteraceae) Cat's Ear. Flower photographed in ultraviolet and visible light. LINK_to_be_added

 

Location: Queensland, Australia

11 Aug 2021

Wildflower

 

Synonyms:

• Hypochoeris radicata L. orth. var.
  

Other Common Names:

• False Dandelion
  
• Hairy Cat's-ear
  

Comment:

My First UVA Dandelion. And it was a false one!

 

Please see Post #17 below for Visible reference photos of this flower.

 

 

Reference:

1. Weeds of Australia (acc 15 Aug 2021) Hypochaeris radicata L.

Editor's Note: I think a "weed" is in the eye of the beholder. Cat's Ear is a wildflower, IMHO.

2. Blum, A.G. (2014) Hypochaeris radicata L. (Asteraceae) Cat's Ear. Flowers photographed in ultraviolet and visible light.

 

 

.

Camera: Sigma fp, full spectrum, full frame, Bayer CFA,

Lens: Canon 40mm pancake lens

Filter: Baader U filter & 20mm macro extension,

White Balance: CWB with teflon/PTFE film on the lens first of.

Lighting: Illuminated with two UVA 365nm LED torches.

 

[ulf]

Nice example of the low saturation that is expected from a narrow band light source like a LED.

The rather short UV-reach of the EF-40mm lens is in this case not the source of a low saturation, as the narrow peak of the LED dominates.

 

I do not think this is a Dandelion though, but some kind of Hawkweed.

I might be wrong as there are many types of Dandelions.

The ones I normally see here has a hollow rather thin walled stem that purge a milky liquid when cut.

 

To identify it better images of the leafs and the flower's rear side is needed.

 

I think there are even more species of Hawkweeds.

For a proper identification we need help form someone trained in botany.

[colinbm]

Here is one off the net of what we have 'down under'....

Dandelion (Taraxacum officinale)

 

 

https://live-product...=862&height=575

 

See Andrea's post below

[ulf]

That Dandelion is common here too, but I think the one you showed in UV is a different type and not a Dandelion.

I might be wrong. It even happens to me from time to time.

[nfoto]

Just a picture of the flower head from above will not help much. The Daisy Family Asteraceae is the largest one of vascular plants comprising 25.000+ species. We need habitus images, ie. whole plant, its stem, foliage, and preferably, the phyllaries ('bracts') underneath the composite head.

 

Whether this is dandelion, hawkweed, or something entirely different, the UV image is pale and lacks the usual contrast these species provide.

[Andy Perrin]

He used torches for illumination which may explain the paleness.

[nfoto]

Paleness of false yellow, for sure, but not explaining the lack of deep black.

[Stefano]

The center should be darker with a wider black area?

[colinbm]

You want it cooked like this.... ?

 

[colinbm]

I try to post my images SOOC with minimal processing.

[Andy Perrin]

Many hawkweeds we have cataloged have smaller black centers. The contrast may be a question of lighting and post processing

http://www.ultravioletphotography.com/content/index.php/topic/893-pilosella-caespitosa-field-hawkweed/

http://www.ultravioletphotography.com/content/index.php/topic/127-hieracium-kalmii-canada-hawkweed/

http://www.ultravioletphotography.com/content/index.php/topic/894-pilosella-officinarum-mouse-ear-hawkweed/

http://www.ultravioletphotography.com/content/index.php/topic/912-hieracium-umbellatum-narrow-leaved-hawkweed/

http://www.ultravioletphotography.com/content/index.php/topic/1236-hieracium-scabrum-rough-hawkweed/

 

[Stefano]

There are a lot of species that look all similar. Dandelion-like flowers are common here, but I am not sure if they are actual dandelions or not. I think mine are a bit darker inside. Some are completely black in UV.

[nfoto]

The center should be darker with a wider black area?

 

Not wider per se, but definitively much darker.

 

As stated (repeatedly) before, Asteraceae is the largest of all families of vascular plants and many of the yellow-flowered representatives appear not false-yellow, but more or less black, in UV. Some species originally described as hawkweeds, now often segregated as the neighbour genus Pilosella, are good examples as most are visible bright yellow and entirely UV black. The exception being the red-flowered Pilosella spp. which sometimes display the traditional false-yellow/UV-black centre.

[nfoto]

You want it cooked like this.... ?

 

 

Colin: cooking requires the right ingredients.

[Andy Perrin]

Colin could have used sunshine and a lens with a wider bandpass but we don’t all use the ideal equipment for every single shot. This one is nice and sharp at least. I assume the trade off was between using a lens with autofocus and one with a deeper UV cutoff. And torch was used to cut the exposure.

[Andrea B.]

Col, just show us the leaves or the entire plant.

[colinbm]

As requested.......

Dandelion patch & Dandelion flower head.....

 

 

 

[Andrea B.]

Cat's Ear

Hypochaeris radicata

 

UVP LINK: https://www.ultravio...icata-cats-ear/

 

Australian LINK: https://keyserver.lu...is_radicata.htm

 

On those green bracts ("phyllaries") underneath the flower you can see a little bit of dark fringe on the tips. That is a key identification point.

 

Note that the Cat's Ear leaves are not the same shape as the leaves of the previously linked Taraxacum.

[colinbm]

Cats Ears, Love-it, I'll have to fill my yard up with them......amongst the Cats Nip I will plant too.....ha ha

[nfoto]

Besides False-yellows, we now have False-dandelions

[Andrea B.]

This topic is about a wildflower, not a cultivar. So it belongs in the wildflower section. I will be moving it to the botanical section if Col would like to make a formal entry. I will check with him.

[colinbm]

Yes please Andrea