We have a quite deep dam approx.10 x 15 m in area covered in a type
of water weed, it is browny red at this time although it was greener
early on, it has a miniature fern like structure... how can we get rid of
it or should we? Does it have any uses? We introduced ducks to eat it
but they don't seem to be…
The water weed is probably a species of Azolla, either A. rubra or A. caroliniana. These species are common throughout the country on lakes, ponds and slow-moving rivers. Often forming a red bloom, they are free-floating, clump forming, evergreen aquatic plants, which can become invasive. It favours shade and exposed sites. If your ducks won't eat it, try feeding it to your chickens instead or use it for composting.