Greater Dodder (Cuscuta europaea) experiment hold mouse cursor on picture for more info and click to enlarge
On April 22nd of 2009 I started a small experiment with seds of Greater Dodder (Cuscuta europaea, Groot Warkruid in Dutch). I had read about the
germination of the seeds of this parasitic plant and wanted to see how this worked. The Dutch Ecological Flora states the following about Dodder
'Dodders germinate in the early summer. The germ plant contains a small amount of chlorophyl and stays alive on it's own strenghth for a short time, but it's
rootlet shows hardly any development at all. In the mean time the sideways curved top of the plant makes rotating movements, sometimes making a full circle
in 15 minutes. When the dodder-stalk makes contact with a living stalk of a suitable host it starts to wind itself around it leftwards. Using 'drillroots' it
penetrates the vessels of the host stalk. From now on it - passively - receives so many nutrients from the host it can sever it's direct contact with the
ground: it's own rootlet and stalkbase soon perish. Further development is aimed at maximum stalk-growth and setting seed.'
Sometime in 2008 I had found a couple of dried out seed cases of Greater Dodder in the Ooijpolder near Nijmegen. Greater Dodder's primairy host plant is
Nettle (Urtica dioica, Grote Brandnetel in Dutch). In it's absence, Hop (Humulus lupulus can serve as host as well. I wasn't planning on
letting Greater Dodder 'eat' our Hop, so I placed one of the small Nettles that grew in our garden in a flower pot. I dropped a couple of dodder seeds on the
soil surrounding the base of the Nettle. I followed the development 'till about mid-May when the young plant died unfortunately. I was however able to follow
the development as described in the Dutch Ecological Flora, which was very interesting.
The pictures I took of the developing Greater Dodder can be found below. Pictures of fully grown Greater Dodder plants can be found on both pages of the
plant pictures section.