[Plant-biology] Re: What strange seed is this??

[Theo Griep]

Thanks to Kay I now know it is Trapa natans.
It seems to be a pest in the US, here in Western Europe it is rare.

http://usuarios.arsystel.com/p.m/c/castana%20agua/castana_agua.jpg

http://gallery.cs.umb.edu/gallery/Trapa-Natans

http://www.invasiveplants.net/invasiveplants/biologicalcontrol/3WaterChestnut.html

http://www.aquariana.be/artikels/planten/trapa.htm












"Theo Griep" <griep at planet.nl> schreef in bericht 
news:42ea9bec$0$12565$ba620dc5 at text.nova.planet.nl...
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> http://home.planet.nl/~griep/seed.jpg
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> These StarWars-like seeds (I'm not sure these are seeds anyway...) where 
> floating in a lake in France.
> As hard as stone, 4 very sharp points each with small hooks on it.
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> Anyone knows if it is a seed, if so from what plant, and why it has this 
> strange shape ('how is it supposed to work?') ?
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> Theo
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