As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.

In article ,
Galen Hekhuis wrote:

As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.

Galen, oxygen (aeration) only promotes duckweed growth.
Was this a way to keep it under control? Forgive me if I didn't get
follow the thread.
Scoop the the stuff out of your pond and be prepared to continue
scooping it out as needed to keep the surface as clear as you want.
Aeration is good for the fish, since if you have any, they are starving
from the lack of open surface due to choking duckweed.
Once again, forgive me if i didn't understand this experiment.

I shovel out a bucket full of water lettuce every week from my miniscule
pond. It's healthy and there's a lot of nutrients in the water, but even
with my aerating waterfall, I need the open surface area for the fish
health.

--
To reply by email, remove the word "space"

Have you thought about using roundup on the duckweed?

Jim

On Wed, 12 Aug 2009 22:01:22 EDT, Galen Hekhuis
wrote:

As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.

Odd thing about duckweed around here. Grows like crazy in some tanks and
not so much in others... oh wait, fish that eat it. ;-) You know though...
even if you have an otter, I bet some goldfish could keep away from it.
Especially if you put in a big school of them. A few dark babies are bound
to stay dark and be safe. What else currently attracts the otter food-wise?
You're just in the hobby of extreme ponding, kind of like those of us who
do extreme bird-feeding (when the hawk visits your bird feeder).
~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

On Thu, 13 Aug 2009 08:18:03 EDT, Jim Hurley
wrote:

Have you thought about using roundup on the duckweed?

From what I've read, Round-up isn't recommended around water. There
are herbicides specifically for duckweed, but I'd rather have the
duckweed than herbicides, I'm just that way.

On Thu, 13 Aug 2009 08:17:55 EDT, Kurt
wrote:

In article ,
Galen Hekhuis wrote:

As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.

Galen, oxygen (aeration) only promotes duckweed growth.
Was this a way to keep it under control? Forgive me if I didn't get
follow the thread.
Scoop the the stuff out of your pond and be prepared to continue
scooping it out as needed to keep the surface as clear as you want.
Aeration is good for the fish, since if you have any, they are starving
from the lack of open surface due to choking duckweed.
Once again, forgive me if i didn't understand this experiment.

I shovel out a bucket full of water lettuce every week from my miniscule
pond. It's healthy and there's a lot of nutrients in the water, but even
with my aerating waterfall, I need the open surface area for the fish
health.

I have a complete blanket of duckweed, I don't see how it could get
healthier. If the extra oxygen helps the duckweed, so be it. I'm
hoping (not certain) that the additional mechanical agitation will
discourage it. I have some reason to believe this by watching time
lapse photos of the pond, but I guess I'll find out for sure during
the coming months. Just as a worthless data point, while I have seen
some of the turtles in the pond actually eating the duckweed, they
don't seem to be effective at controlling it.

On Thu, 13 Aug 2009 15:35:16 EDT, ~ jan wrote:

On Wed, 12 Aug 2009 22:01:22 EDT, Galen Hekhuis
wrote:

As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.

Odd thing about duckweed around here. Grows like crazy in some tanks and
not so much in others... oh wait, fish that eat it. ;-) You know though...
even if you have an otter, I bet some goldfish could keep away from it.
Especially if you put in a big school of them. A few dark babies are bound
to stay dark and be safe. What else currently attracts the otter food-wise?
You're just in the hobby of extreme ponding, kind of like those of us who
do extreme bird-feeding (when the hawk visits your bird feeder).
~ jan


Wouldn't I risk their escape? The overflow from the pond runs right
into the Suwannee River.

Galen Hekhuis wrote:

As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.

Is it discouraging it, or just compacting it? Have you asked
your local county agents [in NY I'd ask Envirnmental Conservation- and
Cooperative Extension folks- don't know what they're called in your
part of the world] for advice? My instinct is that a couple
sterile grass carp couldn't do any harm.

Cornell University, in NY, is always experimenting, so I give them a
call on lots of stuff. I googled for this one and found their pond
page.

http://pond.dnr.cornell.edu/Pond/Com...c.htm#duckweed
They suggest aeration and grass carp.g Guess we covered that.
[they also mention a rake- which I had thought of, but in a more
automated, giant vacuum type device that works when you're sleeping.]

Jim

In article ,
Galen Hekhuis wrote:

On Thu, 13 Aug 2009 08:17:55 EDT, Kurt
wrote:

In article ,
Galen Hekhuis wrote:

As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.

Galen, oxygen (aeration) only promotes duckweed growth.
Was this a way to keep it under control? Forgive me if I didn't get
follow the thread.
Scoop the the stuff out of your pond and be prepared to continue
scooping it out as needed to keep the surface as clear as you want.
Aeration is good for the fish, since if you have any, they are starving
from the lack of open surface due to choking duckweed.
Once again, forgive me if i didn't understand this experiment.

I shovel out a bucket full of water lettuce every week from my miniscule
pond. It's healthy and there's a lot of nutrients in the water, but even
with my aerating waterfall, I need the open surface area for the fish
health.

I have a complete blanket of duckweed, I don't see how it could get
healthier. If the extra oxygen helps the duckweed, so be it. I'm
hoping (not certain) that the additional mechanical agitation will
discourage it. I have some reason to believe this by watching time
lapse photos of the pond, but I guess I'll find out for sure during
the coming months. Just as a worthless data point, while I have seen
some of the turtles in the pond actually eating the duckweed, they
don't seem to be effective at controlling it.

Seems to me that you are trying to dig a tunnel with a spoon.
Even with the most vigorous agitation, there will be some quiet areas of
the pond where the DW will continue to thrive.
I personally don't see how adding oxygen to the water will inhibit any
plant growth. DW may not like moving water, but if nutrients are there,
seems to me it would take a constant tsunami to discourage them.


I'd get a big swimming pool net and scoop to get most of it out, then
see how the aeration experiament works.

I'm with you on herbicides, etc.

Here's the skinny of Roundup:

So What's the Problem With Roundup?
They say: "It's Safer than Mowing"; "Biodegradable";"Environmentally
Friendly"
Some Important Facts You Should Know
? Glyphosate, the active ingredient in Roundup, is the third most
commonly-reported cause of pesticide illness among agricultural workers
in California.
? Glyphosate is the most commonly reported cause of pesticide
illness among landscape maintenance workers in California.
? The surfactant ingredient in Roundup is more acutely toxic than
glyphosate itself and the combination of the two is yet more toxic.
? Glyphosate is suspected of causing genetic damage.
? Glyphosate is acutely toxic to fish and birds and can kill
beneficial insects and soil organisms that maintain ecological balance.
? Laboratory studies have identified adverse effects of
glyphosate-containing products in all standard categories of
toxicological testing.
? Glyphosate residues in soil can persist over a year.
? Glyphosate residues has been found in strawberries, wild
blueberries and raspberries, lettuce, carrots and barley.
? Glyphosate has been measured 1,300 - 2,600 feet away from its
application site.
? This year Monsanto, manufacturer of Roundup, agreed with the New
York Attorney General's office to discontinue their use of the terms
"biodegradable" and "environmentally friendly" in ads promoting
glyphosate-based products, including Roundup.

http://www.ecologycenter.org/factsheets/roundup.html

--
To reply by email, remove the word "space"

On Fri, 14 Aug 2009 08:32:33 EDT, Jim Elbrecht
wrote:

Galen Hekhuis wrote:

As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.

Is it discouraging it, or just compacting it? Have you asked
your local county agents [in NY I'd ask Envirnmental Conservation- and
Cooperative Extension folks- don't know what they're called in your
part of the world] for advice? My instinct is that a couple
sterile grass carp couldn't do any harm.

Cornell University, in NY, is always experimenting, so I give them a
call on lots of stuff. I googled for this one and found their pond
page.

http://pond.dnr.cornell.edu/Pond/Com...c.htm#duckweed
They suggest aeration and grass carp.g Guess we covered that.
[they also mention a rake- which I had thought of, but in a more
automated, giant vacuum type device that works when you're sleeping.]

From what I've read, it seems that there isn't anyone who has a real
answer. The general consensus of opinion is that grass carp eat
duckweed, the sterile variety would without doubt be the best in this
area, but grass carp are not that effective once the duckweed has
taken over. Mechanical control (rakes and the like) is much more
effective, but due to the rate at which duckweed grows, has to be done
rather frequently. My hope is to provide an environment where
duckweed just doesn't like to grow. The agitation of the water by the
bubbler may just do that. Plus, I already had an aerator in another
(duckweed free -- well, mostly water free too) pond. I don't have any
triploid grass carp. I just started with what I had on hand that
might work.

On Thu, 13 Aug 2009 19:07:28 EDT, Galen Hekhuis
wrote:

Wouldn't I risk their escape? The overflow from the pond runs right
into the Suwannee River.

Oh that's right, I keep forgetting that little problem. Even fine screen
wouldn't prevent eggs going down stream. Drat. ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

On 14 Aug, 00:07, Galen Hekhuis wrote:
Wouldn't I risk their escape? The overflow from the pond runs right
into the Suwannee River.

In that case, what worked in my (much, much smaller pond) was to
overflow the pond so all the duck weed merrily ran out of the pond.
However it was much easier for me to arrange than it looks like it'll
be for you. I just sent the rainfall from the roof into the pond for
few months and all the duck weed went.

Matt

Galen Hekhuis wrote:
As requested, here is what the pond looks two days after I threw in
the aerator from the bank.
http://i181.photobucket.com/albums/x...g122009004.jpg
I know it doesn't look like much, but I really don't expect anything
in a hurry. In the time lapse photos you can see the duckweed blanket
move back and forth, east and west, or left and right as you look at
the picture, some 8-9 times a day. In the background, it seems like
cracks may be beginning to form, but maybe it's just wishful thinking.
Hi
In my opinion, the only sure way to get rid of duckweed, is the remove the
nutriants that it feeds on. Funny stuff DW. I've never had it, yet my
mothers pond has masses. How you deal with it in a pond that size, I don't
know. Logically, aquatic plants and manual removal. Good luck.
--
Pete C
London UK