Zone 6 nutrient sink

Hi all,

I've got a pond on property that is downstream of a very slow moving stream that is fed by 15 hectares of conventional farmland. As a result the nutrient load that my pond is taking is downright abusive (among who knows what else). So now I'm trying to think about ways to filter the nutrients as soon as it gets on property using something like a reed bed (not sure about this because of deep freezes in winter) or willow trees (not sure about how effective they can be compared to reeds). I also have questions about how to design something like this. Is rerouting the stream zig zagging around a number of willows enough to pull the nutrient out? Or should it be converted to more of a flood plain/ marshland?

Thansk for your help all

Matt

This sounds like a job for **Mycoremediation**

What I would suggest is to plant the willows AND make sure that the willows are heavily inoculated with mycorrhizal fungi. The combination of the two will do more to remediate nasties in the runoff, than either one can alone. Eventually, if you plant just the willows, they will acquire some mycorrhizal fungi from spores that blow in, but there is nothing like pouring a cup of mushroom gazpacho in the hole when you plant the willow to make sure that there is plenty of fungi there.

I'm glad to help you plan out this remediation project, but I have a few questions:

Are there any willows there now?
Are there any oaks in the area?
What do you mean your pond has been taking abuse? Can you be more specific? Algae bloom?
Have you considered planting bald cypress as part of the water management?
How big is the pond?
Anything living in it? Fish? Turtles? Duckweed?
Are you interested in using the willows as a coppice?

John Elliott wrote:This sounds like a job for **Mycoremediation**

What I would suggest is to plant the willows AND make sure that the willows are heavily inoculated with mycorrhizal fungi. The combination of the two will do more to remediate nasties in the runoff, than either one can alone. Eventually, if you plant just the willows, they will acquire some mycorrhizal fungi from spores that blow in, but there is nothing like pouring a cup of mushroom gazpacho in the hole when you plant the willow to make sure that there is plenty of fungi there.

I'm glad to help you plan out this remediation project, but I have a few questions:

Are there any willows there now?
Are there any oaks in the area?
What do you mean your pond has been taking abuse? Can you be more specific? Algae bloom?
Have you considered planting bald cypress as part of the water management?
How big is the pond?
Anything living in it? Fish? Turtles? Duckweed?
Are you interested in using the willows as a coppice?

Hi John,

Thanks very much for your post and your offer!

To answer your questions:

Are there any willows there now?

-- There are willows in the area, but not there directly, no.

Are there any oaks in the area?

-- None there directly, but about 100m away, yes.

What do you mean your pond has been taking abuse? Can you be more specific? Algae bloom?

-- Yes, exactly. There is a constant film of goop over the top of the pond.

Have you considered planting bald cypress as part of the water management?

-- Haven't considered them, but definitely would!

How big is the pond?

-- The pond is about roughly half the size of an olympic swimming pool in terms of volume and the largest area is about 100m long and 10m wide.

Anything living in it? Fish? Turtles? Duckweed?

-- There were some fish at some point, but I don't know if they are still there at the moment. If I was them I would have swam upstream long ago to escape the nutrients.

Are you interested in using the willows as a coppice?

-- I've thought about that (as coppicing might encourage nutrient uptake?) and we definitely could do that, yes. However I actually would prefer not to with them as this is zone 1/2 and directly in the line of view from our porch.

Hi Matt,

Sounds like you should plan a tree planting program for next spring. Willows and bald cypress can definitely soak up the excess of nutrients, willow being the faster way to go with that. However, to stabilize it over the long run, a few bald cypress in the mix will definitely help. You can start willow with pencil sized stubs, and they can be 15' high in a matter of three years. The tallest I have gotten a bald cypress seedling to get in the first year is about 3'. Then if it has optimal conditions, it can get 5' in two years, and 7' in the third year. It's not a good competitor of other vegetation unless it gets some help, say from a flood that drowns everything else, while it can still keep its crown above water.

Now about the oaks, they will be your source of mycorrhizal fungi. You should inspect them after every heavy rain for mushrooms. Collect up the mushrooms, mix them with some wood chips or leaf litter, and spread this in the area where you will be planting. Almost anything that pops up in an oak grove is a mycorrhizal mushroom.

You might consider stocking the pond with rosy red minnows that you can get at any pet store. They are a cheap native species that are used as feeder fish. They will take care of the mosquito problem and are a step back to a sustainable ecology.

Next question: do you have any plans for water plantings like water lillies?

I actually forgot to mention that I am in Bavaria, so about those rosy reds - do you happen to know what the european equivalent might be? They seem like a fantastic choice for what I need(outside of the native issue).

I hadn't thought of water plantings, but that also sounds like a great idea.

My biggest question around the design here is in which pattern/ structure I should be planting the willows & bald cypress. Is it enough to simply plant them next to the existing stream (the stream itself is about 3 foot depth below the rim where the topsoil is)? Or do I need to move the earth in a way where the water has more exposure to the roots of the tree?

Also, I watched that video you posted about mycoremediation - I love Paul Stamets! The guy is a genius. I saw this or a similar video a few years ago and completely forgot about it. Anyway, in the video at about 10 minutes in, he mentions a technique uses with some kind of myco brick to block runoff. Do you by chance have a link or more info about this technique (or maybe its not applicable to my situation)?

Bavaria! Shows how North American centric my thinking has become with my recommendations. In place of the rosy reds, any local minnow would be a good choice. If you can go down to a local creek with a small net and scoop some up. As far as bald cypress, you may have to check about importing that one. Here in North America, we have two wetland trees, bald cypress (Taxodium Distichum) and water tupelo (Nyssa Aquatica) that I don't think have any European counterparts. The closest thing Europe has to our southeastern U.S. climate zone is maybe the Danube delta on the Black Sea; the wetlands on the Mediterranean just aren't the same.

I don't think any dirt moving is going to be necessary. I think if you get the right plants in the right places, things will begin to heal.


As far as mycofiltration, we have a lively discussion about that topic here.

Hi Matt,

as for the fish eating mosquito larvae in bavaria:

http://de.wikipedia.org/wiki/Bitterling_%28Fischart%29
Bitterling

does a great job eating mosquitos but is a bit picky about water quality, also needs pond mussels for reproduction, which are even pickier

http://de.wikipedia.org/wiki/Dreistachliger_Stichling
Stichling

might be better suited for your needs; more hardy

http://de.wikipedia.org/wiki/Moderlieschen
Moderlieschen

very hardy

also the larvae of dragonflies and diving beetles help a lot, but they will come themselves as long as you have some kind of reeds growing at your pond.

Furthermore it is very good to have a near nesting place for swallows. they do eat a lot of mature mosquitos.

http://www.nabu.de/tiereundpflanzen/voegel/tippsfuerdiepraxis/nistkaesten/01086.html


for the coppicing of willow:

this can be very beautiful actually and you can use the annually harvested rods for basketry, fire wood, fencing,...

http://de.wikipedia.org/wiki/Kopfweide


for the nutrient problem:

if your pond gets its water from some sort of canal it will be very difficult to remove the nutrients because of the change rate of the water and the limited access of roots. in this case (if you are allowed to) you should think about reducing the flowing rate and increasing the surface area of roots in contact with the water. maybe grow waterweeds (non-invasive) in the canal that can serve as a filter and can be harvested and composted in autumn, thereby removing nutrients. also remove big fish (=nutrients). and to avoid future algae bloom (which store nutrients in the pondsoil) shade the pond partially with trees.


I hope I wasn`t too late and could help in some way.

Take care,
Afghani