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Lepidium draba [Hoary Cress]: Norwegian Material


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#1 nfoto

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Posted 29 June 2013 - 20:22

Rørslett, B. 2013 Lepidium draba L. (Brassicaceae). Hoary Cress. Flowers photographed in visible and ultraviolet light. Norwegian material. http://www.ultraviol...egian-material/

Lepidium draba L.
Syn. Cardaria draba (L.)Desv.
NO: Honningkarse
SE: Välsk krassing
DK: Hjertekarse
FI: Kynsimökrassi
DE: Pfeilkresse
EN: Hoary Cress(UK); Whitetop(US)

This is a perennial species, up to 0.6 m tall, native to Eurasia. It is introduced to the Nordic countries where it is naturalised on seashores, waste lots and fallow fields. The shiny white sprays of flowers are in dense terminal racemes and occur in June.

Despite it being considered an invasive weed elsewhere, L. draba is a rare species in most of the Nordic range.

Plants collected at Malmøya, Inner Oslo Fjord, Norway 18 Jun 2012.

Attached Image: LEPI_DRA_B1206182330_VIS.jpg
Image reference: LEPI_DRA_B1206182330_VIS.jpg
Visible light: Nikon D300, Medical-Nikkor 120 mm f/4, built-in ring flash.

Attached Image: LEPI_DRA_I1206184807_UV.jpg
Image reference: LEPI_DRA_I1206184807_UV.jpg
Ultraviolet light: Nikon D40X, UV-Nikkor 105 mm f/4.5 lens, Baader U2" (Venus) filter, SB-140 flash.

The UV features of this specimen apparently are identical to what Blum (2013) http://www.ultraviol...draba-whitetop/ reported earlier.

References::
http://www.ultraviol...ure-references/

#2 Andrea B.

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Posted 30 June 2013 - 19:18

Nice to see L. draba in full bloom. I had to leave Colorado before I could catch one fully opened.
Andrea G. Blum
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#3 nfoto

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Posted 30 June 2013 - 19:24

That was my motivation for posting a sample. Plus adding support to your original observations of its UV signature.

They smell nice as well. Probably the reason for their Norwegian name (Honningkarse = Honey cress).

By the way, i had to single out a small, less impressive specimen inhabiting a sheltered spot. This was a very windy day on the sea and even a flash could not arrest flower movement in close-ups.