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View Full Version : Rudbeckia fulgida var deamii in visible and UV light


Dr Klaus Schmitt
August 12th, 2012, 11:51 AM
Today about another attractive flower, for humans as well as bees: Rudbeckia fulgida var. deamii. Shot outside with natural light (blue sky, no direct sun) in visible and ultraviolet light, using the Baader-U UV pass filter, a CERCO 94mm quartz flourite lens and my UV sensitive camera.

Visible light image:
http://www.pbase.com/kds315/image/145344564/large.jpg

Ultraviolet (UV) light image:
http://www.pbase.com/kds315/image/145344565/large.jpg

Diptych VIS - UV:
http://www.pbase.com/kds315/image/145344566/large.jpg

The petals of this R. deamii variant shows a very distinct "bullseye" UV pattern, invisible for us humans, as many other Rudbeckia species do. Also this one is reflecting around 365nm at its petal tips and is creating a very distinct UV nectar guide for its pollinators.

Asher Kelman
August 13th, 2012, 08:22 AM
Klaus,

An idea just came to me. Birds have ability to respond to UV. It could be that insects that might damage plants would be more visible against the bright background and enable passing birds to pick them off! We assume that birds wouldn't go for there bees!

Asher