When my .15 acre farm pond was renovated last summer there was about 4' a muck in the bottom that was excavated and most was buried under about a foot of topsoil. Some of it must have been buried very well though and now I have 2 areas that were always wet before the dirt work that has "oily" water is coming up and it smells similar to the barnyard. Don't mind the smell but all the grass and clover has died out in these areas. Other wet areas are doing just fine.

I assume this is the muck coming up through the soil. Are there any soil additives that I can apply to speed the decomposition of this muck?

Assuming that your muck was not polluted some how, it should grow plant life well. My 1/4 acre pond was mucked out last year (8 foot deep smelly barnyard muck) and merely pushed over the dam. This spring the drying muck was smoothed over with no top soil covering. It is growing grass (rye and fescue) wonderfully. I used some of the dried muck in the yard in some low spots and the grass is better there than anywhere else in the yard. I don't have any wet spots however, nor have I seen any oiliness.

This is my only experience with muck so take it for what it's worth. I wonder if you plowed it up to help it dry, expose it to some light and air if that would not speed the process up. The only thing I can think of to explain the "oily" water (besides downright pollution)is that plants contain oils and it's possible that areas of your pond muck where made up of more decaying plant matter than other areas.

I can't recommend any additives, but I'd try tilling it up and possibly mixing in some regular soils after it has had a chance to dry out. Of course, leaving it be might prove out before the summer is over.

It's decomposition of organic material. I have a lot of that where I cut out an old overgrown fence row about 17 months ago that went through a wet area and the roots are now rotting underground. Stirring it up will speed decomposition and allow some aeration of the soil. Plants are not growing there because of the wetness making the soil anaerobic and "soured".

With the pond bottom muck I have dealt with seems like it takes about a year of weathering then it will grow anything.


I suspect tillage to introduce air woukd speed the process a lot.

After over 20 months since digging out and 10 months since spreading, my "muck field" now has an outstanding stand of fescue and annual ryegrass. It's thicker and taller than the grass in the undisturbed part of the hayfield.

Tiller it is. Thanks.

Your assumptions are all correct. The "oily water" is mostly likely algae from the buried sludge. It could also be a bacteria that is attacking iron in the water that saturated the sludge and rose to the surface.

Maybe if Bill Cody sees this, he will provide more information. He is the real expert.

Pond muck shouldn't be spread in a deep layer, unless it can be regularly "turned." It is the same as creating garden compost from grass clippings and leaves. It needs oxygen to decompose.

More than likely, the muck taken from your pond was anaerobic. That is, there was a near total absence of oxygen at the bottom of your pond to help break down the organic materials like leaves, dead plants, dead fish, fish poop, etc.) that collected over the years. That muck produces some nasty smelling gases and some of the oily slick you are seeing.

What you experienced is extremely common. Ponds have thermal layers based on the weight of the water vs. temperature. Typically, the lower layers of a pond have the cooler water, which is usually the heavier water. Depending on the surface area, and the depth, this water becomes devoid of oxygen. That is where the dead fish, the fish poop, and the leaves congregate.

Spreading the muck in the sun and air is usually far better than burying the muck several inches below the ground where it gets little oxygen. It is how today's fossil fuels of coal, oil and gas formed millions of years ago.

Even above the soil, spreading it several inches deep will tend to let the sun and wind seal it at the exposed surfaces. That prevents oxygen from penetrating below that crispy cover.

It needs oxygen to decompose into what we think of as good organic compost. Burying it, or spreading it thickly over otherwise good topsoil, keeps it from decomposing to the conditions we would prefer to have on our properties.

In your case, is the area too wet to plow, disc or roto-till? Doing so would help bring it to the surface where it would mix with other soil filled with good bacteria and critters like earthworms. It will get a lot more oxygen. The bacteria and earthworms will start to work on it pretty quickly.

Good luck,
Ken

Cat - I appreciate your comments above and they have me thinking about what has been done at my pond. The dam on my pond has been doubled, maybe tripled, in width from the muck being pushed over. I know in a few places the muck is several feet deep (maybe as much as ten feet). I have been thinking ahead and have thought about putting some shrubs or bush-like trees on the dam side opposite the pond. Will the buried un-decomposed muck be a problem for plants that have deeper root systems? (I'd hate to spend the time planting just to have them reject the deeper soils/muck.)