The white parachute

[Hobbyst46]

Hello,
The seeds of Asteraceae flowers, for example the yellow Leontodon weed (uncertain identification; looks much like Sonchus) spread in the wind by virtue of a "parachute" - a tiny bunch of white hairs. Thick and thin hairs, to the naked eye ? but the photos suggest 5 micrometer thick tubular fibers, which are spun into ropes.
Mounted in PS-CBO (no advantage over glycerol in this case) and sealed with gel nail polish.
Darkfield by means of the DIY LED ring.
All images are single, resized and cropped only, except the 40x DF, which is a stack of 10 images, 4 micrometers apart.

[mrsonchus]

Very nice, 'pappus' 'hairs' - interesting to know which plant they're from.
Do you have an image or any details of the plant they're from?

Thanks for sharing.

John B.

[Hobbyst46]

Thanks John B
It is so abundant, a weed, that I forgot to take its picture... will do that tomorrow.
Thanks for reminding me of the term "pappus" - in fact, kids around call them "grandpa", whereas I am used to the "parachute"...
I was looking for spikes as well and surprisingly found nothing...

[mrsonchus]

That's great, I'm very interested in 'weeds' and wonder about the lack of 'spikes' or 'teeth' on the pappus hairs - the UK Sonchus that I have worked with (S.oleraceus, S.asper and S.arvensis) all have toothed pappi.

Interesting to see the whole plant.

Thanks again, John B.

[MicroBob]

Hi Doron,

beautiful and interesting images! And I see that you have put your new dark field solution to good use - pitch black dark field with the 40:1 n.A. 0,75!
It really is incredible how different nature is when you look closely.

Bob

[Hobbyst46]

Thanks Bob. Hope to provide the flower itself soon...
Yes, I am satisfied with the LED ring. This is a brightfield 40x0.75 Neofluar. I think that for DF, it performs better than the 40x0.75 Neofluar Ph2, like Apochronaut mentioned.
I ordered some denser LED strip (200 LEDs/m) for more experimentation. But breakthrough is expected when MichaelG masters the nano LEDs...

[Hobbyst46]

That's great, I'm very interested in 'weeds' and wonder about the lack of 'spikes' or 'teeth' on the pappus hairs - the UK Sonchus that I have worked with (S.oleraceus, S.asper and S.arvensis) all have toothed pappi.

Interesting to see the whole plant.

I tried my best to identify it, and now think that it is not Leontodon, but rather Sonchus oleraceus.
It is quite tall, 60-70cm. The only missing sign, with respect to the online plant catalogue, is secretion of of white latex when picked (there wasn't any),
but I doubt that is a definitive sign, especially since this plant is known to vary from ecosystem to ecosystem.

To stay within Forum's upload limit I grouped the photos. (1) Whole plant, flower, pappus (2) Another flower, capsule, leaves.
P.S. Although not very clear from the above images, ends of fibers along the bundles actually resemble tiny, very short spikes. But really tiny, less than about 10micrometer long and half as much wide.