Please help me identify this floating plant

[sciencefiction]

Hi,

Does anyone know the name of this plant? Thank you.

 

[BigTom]

Erm, Ludwigia sedoides? Similar anyway.

 

[sciencefiction]

I am not certain. It doesn't really look like it. The leaves of the ludwiga are diamond shaped, this one has triangle shaped ones.

 

[anasarka]

Trapa natans

 

[BigTom]

Trapa natans

That looks more like it.

 

[sciencefiction]

Trapa natans

That's it. Thank you.

 

[anasarka]

Interestingly plant have it in my country and is a protected species. Fruit is very strange, we call it "devil", many years ago used it for food as it is boiled and peeled. Have a taste of sweet potato
http://www.google.bg/search?q=trapa+natans+fruit&hl=bg&tbm=isch&tbo=u&source=univ&sa=X&ei=H-9qUfG5PMbbswbrjIDgAQ&ved=0CD4QsAQ&biw=1366&bih=667#hl=bg&tbm=isch&sa=1&q=trapa+natans+fruit&oq=trapa+natans+fruit&gs_l=img.12...0.0.0.16277.0.0.0.0.0.0.0.0..0.0...0.0...1c..9.img.Q0IVKwIW5Ew&bav=on.2,or.r_qf.&bvm=bv.45175338,d.Yms&fp=59e844069ddfbeb8&biw=1366&bih=667

 

[sciencefiction]

How is it propagated, do you know?
The fruit looks very interesting and big Does it form from the flower, on the surface?
Sorry for the stupid questions but I can't imagine how exactly it grows it?

 

[anasarka]

The plant blooms in June - July The flowers are small, white petals. The fruit is a nut. Powered by the thick black and thick skin. In the fruit has one or rarely two seeds. Propagated by seeds

And do not worry, there are no stupid questions, only stupid answers

 

[sciencefiction]

Thanks anasarka.