"Rusty_Hinge" wrote in message
. uk...
The message
from "DerekW" contains these
words:

Are we confusing duckweed Lemna minor with algal blooms and
filamentous
algae which barley straw does control.

I take it that's a question? I would guess that the OP would know the
difference.

hopefully so but I have heard FA (aka blanket weed and many more) described
as duckweed on many occasions ( by countrymen as well)


We had huge problems on the shoot with a pond being covered with a thick
carpet of duckweed and despite a serious effort to remove it during
which
we scooped off around 60-80 kilos a week over a month or more it came
back
within days.

Arable land nearby? That growth could be due to fertilisers leaching
into the pond.

absolutely right however the farmer is using a low input rotation which I
found amazing, the new wheat and barley varieties have such varied nutrient
requirements he needs to do virtually no addition of inorganics, by careful
selection he can get three grain crops then at the end of the rotation
he'll
drill fodder beans to boost the nitrogen levels and make a small dusting to
add what is lacking and use dry sewage mulch or manure .

This year 2008 it had all but disappeared the only difference being the
introduction of proper pondweed the previous year which has finally
taken
hold and colonised the margins it could be the heavy rain or the weed
reducing the nutrient level or even overspray when our farmer applied
herbicide (unlikely he's extremely careful about when he sprays and
the pond
is about 30 yds from the nearest cultivated area) We do get a lot of duck
but in the covered years they didn't make an impression on the carpet and
they positively avoided the pond we have few frogs ( heron activity) and
no
fish.

I'm told - but haven't tried it - that duckweed is very nutritious and
makes good a soup ingredient. The odd water snail amongst it should
provide a little body...

LOL I'll dry some up and send you a packet of 'cup o weed'
I don't remember Hugh Furry W trying that one and that lad will eat owt

Common Koi and Grass Carp do eat duckweed and I did a little
research and
found freshwater shrimp also do .

The shrimp will eat anything, but you'd need a lot of them.

More the merrier ready for introducing fish the invertebrate levels are
quite good I wouldn't mind adding in mayfly
but as the PH is very low( Mossland) I doubt they would thrive

I'll ask the local head keeper about the condition of his flight ponds
..
bit early in the year for any problems with duckweed our theory was that as
there was no exposed water the ducks were not picking up any reflection when
flighting by at dusk.This no longer the case of course I walked off 4 pair
of Mallard this morning so things look good. Another pond (old marl pit ) in
a depression about 200 yds away which always gets a light amount of the weed
still attracted duck mainly Teal.

DerekW