Forest Gardening in Poorly Drained Clay

Hello, Forest Garden forum!

I'm hoping you can help point me in the right direction. I'm an aspiring young farmer who has come to appreciate the logic behind perennial food production based on natural ecosystems. Unfortunately, the land I have access to is about five acres of flat, flat, flat, poorly-drained, NE Ohio clay. The water table is perched fairly high in spring/winter in many areas, though it dries out sufficiently in summer and fall most years; adjacent property is partial wetland, to give you a sense of what I'm dealing with.

The result of my reading and initial conversations with the extension agent suggest that the drainage issues seriously restrict the forest garden species I can plant with any expectation of success. I know Dave Jacke's book has a list of species tolerant of wet soils, but it is a short list indeed, and does not include important fruits and nuts, chestnuts in particular.

I have debated subsurface drainage, but there is no outlet without crossing multiple property lines, and in addition to the costs involved I would be concerned about planting a food forest over/near tile anyhow. The county maintains a large network of ditches to provide surface drainage, but none cross this property. Essentially, the water has nowhere to go.

I've heard some permaculture folks say to let the land tell you what it's trying to do, and allow it to do that, but that means planting the few, less desirable, less useful species that can tolerate the soils. I'm not quite ready to do that yet, so I'm hoping someone has an idea on how to improve this situation.

In trying to wrap my head around this challenge, I've considered a system of swales and berms, but was unsure of their value on such flat land and with such poor drainage. Hugelkultur mounds seemed like an option, even given the enormous amount of wood I'd have to collect, until I read a number of posts on this site suggesting that trees do poorly planted on top of hugels. Could subsurface/surface drainage make enough of a difference, if I could find an outlet?

As someone with little experience in these matters, I appreciate any feedback you folks can give.

Thanks,

Andy

As you're speaking of drain-tiling and building berms swales and hugels I assume you have a budget/access to equipment to do earth works. Is one spot of your land a bit lower than the rest? Have you considered digging a pond there, and drain tiling the rest into it?
There have to be some plants that will do well in wet soil and really suck up a lot of moisture to dry it out. I wonder if bamboo would do this? Maybe plant that around the perimeter of your land, it would serve as a windbreak and absorb water as it flowed into the lot, thus allowing your drain tiles to have less water to remove to the pond.
If you could post a panoramic view of the lot and maybe a satellite image, we could see the contour maybe?
I'm thinking you could look at the micro-contours of the ground, and trench out a waterway in every lower line you could find, down past water depth. Water with air exposure evaporates quicker than water under dirt, and you could plant water specific plants in them to use up the water, leaving 'islands' if you will higher and drier. And you could harvest whatever grows in the waterways for biomass to build soil on the 'islands'.

This sounds like a very low oxygenated soil situation. Being that you are near the great lakes I'm going to say your rainfall is considerably more than mine. I'm on hard grey expansive clay except my precipitation puts me in the sub arid category where you have probably double the precipitation. As someone living on a flat prairie, I sympathize. A dugout at the lowest part better be part of the plan with a generous overflow. The point here is this is what I would consider maximum difficulty as soil and elevation work against you. If trees are not going to cut it I'd bet you that land would make a killer marsh! The neat thing about marshes is that with the right flowers you can turn your property into a bird watcher's paradise.

If it were my property I'd grow a mix of tillage radish and clover to break up the soil and add green manure to it. Tillage radish is great for breaking up clay and their root draws earthworms to the area just like daikon radish. The goal here is to work with clay, treating the soil like a multi year prep as you would a garden, adding organic matter until you achieve clay-loam.

From there your observation of where the melt water forms and pools will be key, where the depth is minimal and where it is deeper. Deep areas are for water loving species like willow/poplar (many varieties available) and alder. Pay attention to where the alders weaken as this is the ash-basswood zone. If you could get soil respiration developing I'd move to sugar maple which is a very beautiful and fun tree. Presumably I'm thinking you would like to get here directly but sugar maples run out of breath in hard clay. That leaves boxelder.

Cutting corners you could plant two types of maples. If the sugar maples die there most likely isn't enough soil respiration. Then you have to turn to Ohio buckeye and Boxelder maple which is what I am forced to work with. This isn't going to be easy and the point to working with clay is that changing it is a multi-year commitment. My mother proved it can be done and what you end up with is something that holds minerals and water very well so once it is is in the happy zone it takes minimal inputs but getting there will be a challenge.

im in ashtabula county in the pymatuning lowlands. . . very wet . . . . hard brown/streaked red clay. . . . we are mostly wet in the winter and I mean wet. . then summer can be dry.fun
we have had good luck with a few of the trees mentioned above. . . willow. . actually pussy willow and black willow grow everywhere. . . many of the alders grow really well and fix a lot of nitrogen. . were growing a lot of the sitka alder because it stays short. . there are staghorn sumac, grapes, juneberry, arrowwood viburnum, multiflora rose, norway spruce, silky dogwood, pin oak. . . ash, especially green ash. . we have a lot of shellbark hickory, hornbean, witch hazel, apples, and black currant in the forests surrounding our fields. . . . poplar and silver maple grow like gangbusters. . . were about to plant a bunch of sweet sap silver maples from st. lawrence nurseries. . elderberry grow really well. . . we have had luck with apples and pears in the last few years. . .my dad planted a bunch of bush cherries a couple of years ago that are going strong. . .
subsoiling helped tremendously in the first few years. . made it so we could actually work in the spring. . . took 2 yrs or so. . we went down from 6 to 12 inches
all of our hugelkultur experiments have been a success. . .many perennials that we could not grow before will now overwinter because they are high and dry on the hugelbeds
we have ponds now but have plans for more. . .chinampas and fish farming hopefully for the future. . we also have plans for more bees.. ours have done really well. . .i think the extra water in the landscape gives us more and extended blooms in the spring
last year no watering in the veg garden
if you can soak in all that water through the winter the clays will hold it much longer than many other types of soil. . . especially if you mulch and do all the permaculture stuff with permanent groundcovers n such

Andy, I have a link to my blog below. I have been working with super high water table area in NC Michigan..similar to yours with a lot of grey clay ..some areas over 10' deep.

I am in NW Pennsylvania, a little south of Erie and I have been researching my soil. My yard, like yours, is flat, flat, flat. What I am finding in my research is that my soild structure was created when the glaciers came through. There is a layer from 7-17 inches that is what they call till/loam with a decent amount of structure that has a little size to it (definitely not sandy). Under that is something that they call fragipan. What is happening in my area (and I suspect yours) is that the water table tends to be quite high (in wet season they say from 6-18 inches below the surface) and it sort of sits on top of the fragipan in the wetter time of year. The fragipan layer makes it very slow to percolate the water through.

I am trying to figure out if subsoiling (sort of like plowing, but a lot deeper) would be of any benefit to break up the tough fragipan layer and allow the roots of trees like fruit trees to better permeate it. From what I have read so far, it appears that the roots of trees tend to take a sideways path unless they find a crack in the fragipan that they can grow down through. My only concern about subsoiling is that some people have said that the ground will eventully revert back to what it started as unless A LOT of compost and other natural materials is continually added. I would think, if you are growing a forest, that would not be a problem since part of the idea is to continually ammend the soil.

I guess I wonder if subsoiling would work long enough to get fruit trees well established in the fragipan (dense/brittle/non-permeable) layer and, if they do become well established, if they would then help the overall drainage of the site since that layer would be "broken open", so to speak. One of the early on challenges would be to make sure that the fruit trees have enough initial drainage when planted so as to not rot the root system when the weather is wet.

I don't know if any of this helps or adds more to the question, but I thought that I would comment anyways. I initially thought that my soil was very heavy in clay and extremely compacted, but as I do more research, I am finding out more about the structure and am scratching my head a little as to how to best deal with it when creating a food forest/permaculture site.

Whoa! Thanks all for the thoughtful replies!

C Englund - I had thought of a pond to drain into, but didn't know tile could drain into a pond on such level land--wouldn't it back up or just sit there in the pipe? I like the idea of soaking up some of the water with water loving plants--maybe hybrid willow or poplar instead of bamboo. The idea of creating "islands" with low spots is really appealing as well. Wonder if something like one or two bigger ponds to drain into, then a series of wetland cells/microponds scattered around would serve the purpose. Would also probably create some interesting microclimates, and a lot of wildlife habitat.

Collin - I think you're right about the soil oxygenation--it can be fairly stinky (anerobic) when you're digging around in wetter areas. The sense that I get from what I've read and what you've posted though, is that with the right species and the right techniques, clay can be opened up a bit and encouraged to breathe, and maybe drain some more. Just a difficult soil to work with, and you pay for mistreating it. At best, I know I can grow sugarmaple here--they're weeds in the woods nearby, and there'd be worse things to have than a sugar bush!

Hisako - Whoa, sounds like you've got a lot going on a few counties over! I'd never heard of sweet sap sugar maples--very interesting story on the St. Lawrence Nursery site, going to have to buy some to grow in the wetter areas. What sort of subsoiler did you guys use? I've been asking around to see if anyone owns a Yeomans plow, but they're unheard of in these parts.

Brenda - Interesting blog--looks like you've got a lot of projects going on. Saw the hugelbed you made--it's huge! The water table is even higher on your land than mine, though--don't envy that.

Jen - Sounds a lot like the problem I'm having, and I do think subsoiling might help, if it's deep enough. I think tree roots eventually being into the soil will help keep it open to some extent, but as I'm learning, only so much can be done.

Some great ideas, folks. Going to have to spend some time trying to synthesize and see how these pieces might fit together. If anyone else has suggestions, I'd be glad to hear them!

We also have heavy clay with a little bit of slope. Here's what works for us so far. Black Walnuts (we have around 40 Carpathians but they seem to be really slow), highbush cranberry (make sure you get the right kind), currants do well, and even our Chinese chestnuts are doing OK. This spring we are going to try river cane (we have bamboo, but it takes so long to get going) with ostrich ferns mixed in. This year we will also try Swiss Stone Pines, the description at Rhora's says they do quite well in heavy clay. Korean nut pines didn't do very well at all. Goumis, Aronias and wild strawberries (we had to work the soil a bit) are also doing well, the aronias so well that we put in another 30 this passed fall. Good luck on your projects. We are Z5 in the Fingerlakes of NY

I also have Poorly Drained Clay in Cincinnati Ohio. I have the same issue with water table in spring and late fall.
However, I can grow mulberry like anything. In fact this year I am looking to purchase an assortment of mulberries.
The fruit can be eaten by the chickens, pigs, etc. And if you do a little research you will find that the leaves and branches are used as fodder trees around the world.

Hi Andrew
try to find out what the local native flora is, for clay soil, in your area, the grasses, herbs forbes and sub shrubs, as well as pioneer trees there will be local native species that thrive and others that in time will/may go deep and break open the soil, encourage these first, collect seed and plants and work with nature.
Forest has to start somewhere and usually in nature there are years of other non tree species that start/ pioneer a soil before forest is employed.

some may even be edible or useful. Burdock? as i dont live in US, so I cant recommend any, but species such as fiber producing plants should grow well on clay, as its rich in nutrients.
Also many plant species that gain biomas on clay can feed other animal species such as chicken or ducks, you could grow these plants to abundance , there are salix =willow spp, even some that are shrubby and low growing, or alder, both attract large numbers of creepy crawleys that the ducks can get feed on.
poplars and eucalyptus may help drainage esp the evergreens as they transpire water in winter as well.
I live on upland Gley, worse than clay, its about zone 7 and cold and damp, short season, mostly growing food is a joke, unless in poly tunnel, even when it does grow outdoor we get plagues of slugs, up the trees and bean poles, so, we grow trees for fuel, leafy food grows okey, ,herbs and wildflowers, any plants just for the hell of it. if they grow..
we get some fruits from more tender trees, but they rare, only in hot summers 2 in every ten years, even apples can be ruined by late spring frosts.
the first plot of land that I worked has matured into tall past pole stage trees , forming sun traps and the soil has hugely improved,
originally after advice from Bill Mollison, i got in a heavy track digger machine to terrace the gley, raising soil in large wide beds {from 5 to 10 metres wide}and digging swale like trenches. for drainage. both have worked, the trenches get naturally full of wet leaf litter and the raised areas, some 1000 metres in area size have all become easy to work and well drained. yes my site has a slope, but I am allowed some luxury!!!
After the initial pond digging and land forming I banned any tractors and heavy animals from the soil to protect its structure, even though next doors cattle and horses sometimes get in past the fence, the soil is worm rich and far lighter after 20 years,
but now , 20 years on, that the land has recovered from 100 years of neglect, deforestation and peat cutting and later growth of rushes, the larger broadleaf weeds are re-invading, as they like the better soil.
there are also usefull, nettle, wild garlic, varied grasses, and more.
once clay is opened up and the soil raised up, over the water table then most things should flourish

was this area ever industrial farmed?(ha, which is funny, because, the whole midwest was at one point.. at least was clearcut and the soil's health went with it). SO, that said, i'm sure, truly, the issue there is like anyone, dealing with restoring the land, which takes time. Earth's timeline is much longer than our, nature talks in hundreds of years, we talk in seasons(or singular years). However, we can speed this process up with the right techniques.

I would consider one of two things, getting the right plants in there to deal with the heavy soil and drainage/water table issue.
OR
do some heavy earthworks, and if its as flat as you say, stick a big pond in the center(or south end depending on site) and use the soil from the pond to build a hill draining to it with swale systems running downhill.

The earthworks method would be a lot more intensive and costly, but, would give you immediate results.

The soil restoration method wouldn't really cost anything more than time as you could find seeds(weeds, from trees in the area, friends, etc), but would take much longer to make happen.

So i guess its up to you, but thats what i'd do.

Have you thought about chinampas?

http://midwestpermaculture.com/2012/12/chinampas-gardens/

On the "hunting Club'', I used to belong to the area had been extensively farmed before reverting to hard wood scrub growing to mature forest,

We had a series of Commercial Loggers come in and make deep ruts across 100s of acres, they didn't care as long as they got their logs out ,
drainage problems multiplied where there had been none before !

Our first lucky happen-stance occurred when we dug a what was supposed to be a deep pond, the guy running the excavator dug down to the
specified depth and completely through the clay bottom ! The second happen-stance occured when an old beaver dam failed and scoured out
a trench down through the clay !

We discovered that nowhere on the club was the clay layer over 20'' deep, just cutting trenches without tileing has solved all the drainage
problems the club has attempted to solve since !

They also went to loggers that log for the club in the dead of winter when the ground is frozen ! They also use the services of an Amish logger
that uses horses !

I dont know if its possible that your property sits on an old lake bed and the clay bed under your property is of shallow depth, but a rental gas
powered post hole digger might just give you back 1/2 or more of your property if it proved your clay was shallow enough to get through the
clay to gravel or sand, like happened here ! Good Luck !

For the future! PYRO AL ! - As always, your Questions and Comments are Solicited and are Welcome ! A. L.

Andrew, If you want to get some trees established in a swampy wet spot, I have just the thing -- bald cypress. If you have some natural swales or low-lying areas, bald cypress will thrive where everything else gets root rot and drowns. You may have to mulch them extra well the first couple winters, because they need to establish a good root system below the frost depth, but once they do that, they can survive quite cold winters. They can be found in all sizes from nursery supply stores, but if you would like to try to start some from seed, send me a PM and I will be glad to send you some seeds.

Don't forget that you can graft Winter banana apple onto malus fusca, our native Oregon swamp crabapple, then graft any other apple onto it. Supposedly, you can graft pears onto it as well, but I can't guarantee long term graft compatibility. Malus fusca is available as root stock. Google it.
John S
PDX OR

funny you would say that about the water table being higher here, there is a hole beside my new hugelbed, where something sunk away I guess..about the size of a baseball, and i can see water in there even on dry days, about 2" below the surface..so yup..I have a lot of water in that area.

NW Ohio, Zone 6a

I'm in NW Ohio in the Toledo Black-Swamp area, and the whole area is the lake bed of glacial lake erie. As such it is all FLAT FLAT FLAT!!! And its all deep heavy poorly drained clay. However, this is not terribly different from the Red River Valley of North Dakota (originally a NoDak), and the way they recondition farmland is not with trees to break up the fragipan, but with deep rooted prairie grasses! Think Sorghastrum Nutans, Big Bluestem, timothy, bermuda grass, and a number of others of similar ilk. These all have roots that go down about 10ft into the soil even in heavy clay, and will form percolation channels for the surface water to drain through. Of course the problem with this is that you then are left with incredibly tough praire-sod (the same stuff people used to build houses out of not too long ago), so good luck tilling it under! (Sub-soiling might be a better idea, but if you're not in a hurry, and you're not trying for profit then this could work too) That said the land will most likely always be a wet spot, and should be treated as such. There are many vegetable and even grain and fruit crops and a few trees too that greatly enjoy wet-yet-well-drained soil conditions. Hawthorn, Cherry, squash pumpkins and really nearly any vegetable crop will do amazingly well on heavy wet soil (so long as its not saturated, grasses in between the rows can help to greatly reduce the soil water content both by breaking up the soil and by drinking and transpiring the water). Sugar maple is good as was already mentioned, in your area Paw Paw might do alright, most of your nut trees will love the sort of heavy "bottom-land" type of soil that you have, and many can tolerate quite alot of water logging. Elderberry is fine with wet soil, some grape varieties will do okay, mushroom culture would be advantageous to introduce a lot of degraded cellulose fiber into the soil to loosen it up. Blackberries, raspberries, blueberries (if your pH is right), asparagus, walnuts, hazelnuts (although watch out for filbert blight since you're out east here), Sassafras tends to like relatively heavy wet soils, garlic grows wild out here around Toledo (Crow Garlic actually, its actually a different species but it tastes nearly the same only a bit milder and it can handle the very wet soils we have), if you like beautiful flowers marshmallow is an obvious choice, or even north american water lotus Nelumbo Americana. Then you've got plants like staghorn sumac, and prickly ash that can be sold to the ethnic foods markets around here.

Anyway there are plenty of profitable plants to be grown in relatively wet soil, but what you need to do to get it from being outright swamp to being useful, is to first (like others have said) dig a pond (preferably with an outflow or at least with some cottonwoods or cattails to evaporate the water), then trench and mound the land in ~3 to 6ft wide trenches and 10-20 foot wide high spots (can be flat doesn't need to be an actual mound, just needs to be about 1-5 ft above the water level in the trenches depending on the plants your growing). Then you can put some lotus or cattail or even wild rice and mosquito fish (or bass, crayfish, or whatnot) into the pond/trenches and pretty soon you'll have a productive and healthy ecosystem again.

Great answer Ole. Du kan scrive fint! Very helpful ideas. I may use some of them myself, even though I don't have quite the water problem that the OP does.
John S
PDX OR

This might be a bit too basic for your site, but this is what I've been up to for the last few years in my heavy wet clay.

When I plant a tree that needs good drainage (like citrus) I just make a big old mound of soil, compost, and woodchips, about 2' high and 10' diameter, and plant on that.

When I need more soil to make mounds, I dig another pond

I don't know how this would work on a larger scale, but it's a good backyard method.

I came across Daniel Brandt today. Ohio no till cover crop farmer with a clay pot factory for a neighbor. Started with yellow clay at half a percent organic matter. Forty years later he is at 7.5 percent. Done with cover crops.