NikonGear'23

Images => Nature, Flora, Fauna & Landscapes => Topic started by: rosko on March 16, 2016, 15:50:44

Title: decayed petals.
Post by: rosko on March 16, 2016, 15:50:44
They come, I think, from Hydrangea flowers.

Back lit (incident sunlight).

Dark vertical background, and a slate as support.

Stack of 2 images only. helicon focus.

Df+Leica 60mm micro elmarit @f/16 (don't trust exifs as there is no mechanical connection).
Title: Re: decayed petals.
Post by: Jakov Minić on March 16, 2016, 16:24:48
Francis, gorgeous!
Title: Re: decayed petals.
Post by: rosko on March 16, 2016, 17:10:28
Thank you Jakov ! :)
Title: Re: decayed petals.
Post by: John Geerts on March 16, 2016, 17:39:56
Really beautiful, colour and details.
Title: Re: decayed petals.
Post by: Bjørn Rørslett on March 16, 2016, 18:57:05
Hydrangea it is. Really interesting and tasteful treatment on the subject.
Title: Re: decayed petals.
Post by: rosko on March 16, 2016, 19:44:33
John, Bjørn, thanks for commenting ! :)
Title: Re: decayed petals.
Post by: Frank Fremerey on March 17, 2016, 11:03:54
Perfect abstraction through: light, background and wind control ... textbook quality .. wow!
Title: Re: decayed petals.
Post by: Jørgen Ramskov on March 17, 2016, 17:17:07
Oh, that's very well done. The small bit in the top left corner do annoy my eye slightly though.
Title: Re: decayed petals.
Post by: rosko on March 17, 2016, 18:29:53
thank you Frank and Jørgen !

@Jørgen : I didn't even notice it ! ;)
Title: Re: decayed petals.
Post by: Jørgen Ramskov on March 17, 2016, 20:17:49
At first I thought it was something on my screen :)
Title: Re: decayed petals.
Post by: Akira on March 17, 2016, 21:16:06
Francis, I appreciate your keen eyes to spot this beautiful object in the first place!  The lighting is fantastic, too.

Sorry to nitpick, but they are decayed leaves and not the petals...
Title: Re: decayed petals.
Post by: rosko on March 17, 2016, 22:34:31
Akira, I know it can be confusing, but they are really petals : each one are florets of Hydrangea, and each floret have 4 petals. many florets compose the big spherical flower head.

My picture shows 3 florets.

That said, I agree that they look like Leaves.

Thanks for your kind comments, ;)
Title: Re: decayed petals.
Post by: Akira on March 17, 2016, 22:44:02
Francis, thanks for the clarification.  I knew that the construction of Hydransea is different from that of usual flowers, but I took it for granted that these were the leaves.  I didn't know that the florets would look like these when they are decayed this far.

Thanks, again, for reminding me of yet another wonder of the nature.
Title: Re: decayed petals.
Post by: Bjørn Rørslett on March 17, 2016, 22:55:08
You both have glimpsed a part of the truth: these are part of the floral structure, but really are sterile leaves that have been enlarged to maximise floral visibility. Thus in botanical terms they are bracts.
Title: Re: decayed petals.
Post by: Bjørn Rørslett on March 17, 2016, 23:05:12
Here is a view of the inflorescence of Hydrangea petiolaris and one can easily see the showy bracts and the modest ordinary flowers.

(Rosko: excuse my butting in on your thread)
Title: Re: decayed petals.
Post by: rosko on March 17, 2016, 23:29:48
Ok, I see !

I had already noticed there are 2 different sorts of flowers on this plant. I didn't know about sterile ones.

So, this is why the structure persists : true petal is more delicate and fragile while bractée is tougher/coriaceous.

Thanks, Bjørn, for this clarification !
Title: Re: decayed petals.
Post by: Bjørn Rørslett on March 17, 2016, 23:37:19
Actually, depending on the species, there might not be petals at all, just the bracts. Also do note that the normal flowers, ie. those without bracts, have large nectaria. You can see the glistening nectar fluid oozing out of the nectaria in my picture.
Title: Re: decayed petals.
Post by: Akira on March 18, 2016, 03:10:36
Bjørn, thanks for the explanation.  I'm always fascinated by the way different species develops themselves differently according to the environment.
Title: Re: decayed petals.
Post by: rosko on March 18, 2016, 09:05:10
Akira, I have to apologize for the peremptory way I answered to your comment : bract is not petal, even I it looks like petal (shape, color, etc.), and even if it is called ''floret''. ???

So the structure left after a whole winter is probably cellulose, a vegetable fiber which constitute the skeleton of any plant.



Title: Re: decayed petals.
Post by: Fons Baerken on March 18, 2016, 09:10:39
the infertile flowers that lure the insects
Title: Re: decayed petals.
Post by: Akira on March 18, 2016, 09:14:15
Akira, I have to apologize for the peremptory way I answered to your comment : bract is not petal, even I it looks like petal (shape, color, etc.), and even if it is called ''floret''. ???

So the structure left after a whole winter is probably cellulose, a vegetable fiber which constitute the skeleton of any plant.

Francis, no worries!  This little discussion was very fruitful.
Title: Re: decayed petals.
Post by: rosko on March 18, 2016, 09:35:56
the infertile flowers that lure the insects

Well, I don't see what purpose for, if the flowers are no fertile ? They may attract insects from very far due to their size and then eventually insects land on scented fertile flowers...That is an assumption.
Title: Re: decayed petals.
Post by: Akira on March 18, 2016, 09:40:28
Well, I don't see what purpose for, if the flowers are no fertile ? They may attract insects from very far due to their size and then eventually insects land on scented fertile flowers...That is an assumption.

My wild guess is that the bracts either reflect or absorbs UV to guide the insects to the central part of the flower head.  Or, they just function as intermediate steps for the pollinators to crawl onto the flower head?
Title: Re: decayed petals.
Post by: Bjørn Rørslett on March 18, 2016, 12:27:02
Human speculation on the ways Nature operates and functions tends to be futile and a waste of time. We can only assume that because an entire genus with 70-80 species share this structure, it does not prevent natural selection and evolution .... Besides, even bigger genera such as Euphorbia (spurges) have even more advanced variants of the same underlying principle.

UV photography indicates the sterile bracts are moderately UV reflective and that the nectaria are UV bright. They also fluoresce under UV. The entire Carrot familiy (Apiaceae) shows the identical pattern.
Title: Re: decayed petals.
Post by: Fons Baerken on March 18, 2016, 12:43:15
you are basically saying the same thing ,
refrasing a similar assumption, amazed i am one takes words for absolute
rather than relative or provisional really
Title: Re: decayed petals.
Post by: Bjørn Rørslett on March 18, 2016, 13:15:20
Thus we all reach unison agreement. Good for everyone.
Title: Re: decayed petals.
Post by: Gary on March 19, 2016, 05:09:30
Great viewing and interesting read.  Thank you all.   :)