Mistletoe UVF

[Adrian]

This is the Mistletoe (Viscum album) a parasitic plant of several tree species in the UK. It inserts it's "root" technically called a haustoria into the stem/branch of the host tree. This is a UVF image of the mistletoe haustoria and host stem. I am not a botanist so cannot ID also the various tissues here (? Birna), but an interesting result!

The section was cut carefully with a scalpel. It is approx 5cm from top to bottom of the image. 

Technical: UVF: Nikon D850 with 105mm micro Nikkor lens. Light painted with UV "Nemo" torch, 5 seconds at f/22

[colinbm]

Nice exercise Adrian.

[nfoto]

Very nice illustrations, Adrian!

 

Yes, Viscum sends haustoria (sucking 'roots') into the phloem, the section of the stem tissue that transports sugars and other stuff throughout the plant. Since Viscum is green and has chlorophyll, it is technically "only" a hemiparasitic species.

 

Perhaps you could split the mistletoe stems too? would be interesting to have a peek inside.

 

Alas, very few locations for V. album in my country and getting a sample would require hours of driving. Oh wait, the species is protected by law, so would strictly break the law if I dared to sample my own specimen. The protection extends to the host tree as well, much to the annoyance of people getting their garden trees infected.

[Adrian]

Birna- thanks for your comments. I will have a look at the mistletoe stem later. Mistletoe seems to be increasing in the UK, with birds such as Blackcaps spreading the seeds more widely. Blackcaps used to migrate each winter, but more and more are staying in the UK with our warming climate!

[nfoto]

Only a very small part of Norway is warm enough - so far - to allow mistletoe growth. But it is slowly expanding its range. We do know it was wider distributed in the Postglacial warm period approx. 5000 years ago. Pollen samples from bogs proves this.

 

The species is not protected in the UK then?

[Adrian]

Birna

This particular specimen was taken from a "street tree"which was blown down last week by Storm Eunice. In the UK Mistletoe is actually farmed for the Christmas market, and large amounts are grown in the western part of England. It provides a good income for fruit farmers who encourage it in their orchards.

Here is the stem of Mistletoe in UVF:

[nfoto]

The reddish fluorescence might be from the phloem. You might look into the various quick tests for sugar in plant sap. 

[Nate]

This is very interesting, great pics. I must research this more on  How/Why  Mistletoes do this.

[Cadmium]

Very nice!  :-)

 

[Doug A]

Superb images and subject @Adrian. Mistletoe is recognized as beneficial, but not protected in my location ( Missouri, USA). 

 

Thanks for sharing,

Doug A

[Andrea B.]

Very cool presentation, Adrian.

I had never read about how the haustoria, so this was interesting to learn about. 

We have some mistletoe occasionally parasitizing the juniper shrubs around here. (Juniperus monosperma.) Our mistletoe is of the Phoradendron species, sometimes called Leafy Mistletoe.

[Bill De Jager]

Excellent work and fascinating results, Adrian.

 

Mistletoe is never beneficial to its host though the leafy types do provide food (berries) for birds.  The berries are quite toxic to people.