Gene Logsdon and Friends

The Virtues of Virgin Soil

In Gene's Weekly Posts on July 10, 2013 at 7:18 am

vg

From GENE LOGSDON

My wife’s mother followed an annual ritual of going to the woods and bringing back a bushel of dirt to use for potting soil. Carol, as a little girl, went with her to help carry the heavy basket back. Others tell me of similar memories, the woods soil being used not just for potting but to add to raised beds of city gardens to increase fertility. Folklore if not fact has always believed that virgin soil has almost magical qualities of fertility. I have a hunch that readers of this blog know of this custom or maybe still follow similar practices.

There are plenty of specific agronomic studies comparing virgin vs. farmed soils, almost all indicating more biological life in virgin soils. But the studies are couched in the impenetrable language of soil science— words five miles long— and do not come up with the kind of firm or even tentative conclusions I am looking for— whether or not virgin soils have superior nutritional or productive characteristics over soil cultivated for a long time but kept fertile with modern farming practices. I presume that scientific farming interests aren’t particularly eager to do research that might show that soils suffer from being cultivated, even with all our scientific knowhow.

In my research, I was lucky enough to stumble across Ronald Amundson, Professor and Chair of the Department of Environmental Science, Policy, and Management at the University of California, Berkeley, and also a Fellow of the Soil Science Society of America. He speaks in a language I can understand (probably because he grew up on a South Dakota farm and has worked the soil himself). Like me, he is much intrigued by our remaining virgin soils. “I suspect that the biology of virgin soils has more diversity and abundance compared to farmland, but I do not know yet of any microbiologists who have really studied the issue,” he says in an email. “I have been trying to get funding for such a study but times are tight now.” Then he added, most significantly in my opinion: “Our soils have been forming for over 10,000 years. We highly value 5000 year old trees but think little about completely changing something much older.”

Farm science seems to think that it can remake in a few years or sooner soil as good as those that took 10,000 years to form. I wonder. Some years ago I was walking with a friend across his farm when he asked me if I could see anything peculiar about his wheat field. Part of it was a little greener and taller than the other part, as if they were different varieties, or planted on different days or with different amounts of fertilizer. No, he replied, the only difference is that one side of the field was cleared 40 years ago and the other 80 years ago. This was particularly significant, I think, because he has always treated his land gently, always keeping it in long rotations with green manure crops as well as using careful applications of commercial fertilizers.

On my own little farm, I have about four acres of woods— old growth forest underlain with virgin soil. I have often noticed how much more vigorously plants seem to grow there even in the partial shade of the trees than they do in my fields that have been farmed for 150 years. Peach trees especially— a story I’ve told here a few years ago. Burdock leaves grow so big that one of them would be enough to wrap a baby in. Giant ragweeds really become giants, to 15 feet tall. Lambsquarter grows above the chicken coop roof. Needless to say, all three of these weeds have nutritional or commercial value. (Have you ever tried stir-fried burdock roots?)

There are records of 200 bushel corn grown on new land in the Midwest in the late 1800s even with low-producing open pollinated varieties, but average yields went down to 40 bushels per acre or less until hybrid corn came along. Wouldn’t it be interesting to know what would happen if today’s highest yielding corn varieties were planted in soil never touched by the plow? I intend to try it next year. I’ve even found an old account of how pioneers planted corn between stumps on newly cleared ground— with a dibble stick. I’d appreciate any thoughts you readers have about this. Or results from similar experiments. I am wondering if we shouldn’t be paying more attention to what’s left of our virgin soils.
~~

  1. When I was a kid (I’m in my 60s now) I would go out into the woods with my old aunt and get several buckets of woods dirt for her violets and christmas cactus. She was always giving those away as birthday presents and so on. Everybody wondered what her secret was that those plants did so wonderfully crazy well in growing and flowering. She always just cackled and said, “Nuthin to it Dearie, just good old healthy dirt…”

    I’m convinced this is the main reason so many permaculturists are bonkers over creating food forests. The entire process replicates the succession of species and creates widely diverse communities of companion plantings fully integrated with animals. It always comes back to the health of the soil, all those bacteria, bugs and mycelium networks.

    I don’t remember if I’ve posted this link before, but this is a classic example of how it works. Plus, if it will work this well in Jordan, with killing heat, dead salted toxic soils and 15 inches of rain per year, imagine how well it would work in a rain rich environment such as so many of us have here.

    Warm Regards, :-)
    Carmine

  2. When I was in commercial agriculture I did see something pretty amazing. A farmer I worked with had a 200 acre river bottom field that had been planted in corn from the time it was cleared. (at least 40 years) He reluctantly planted soybeans on this land. The beans grew to four feet tall and the leaves were at least 5 inches across. I have never before or since that time seen such a response. At the time (1993) I assumed it had to be the lack of disease presence. I say that because the lower leaves of those beans never developed any disease symptoms that normally appear on soybeans. His harvested yield was in excess of 65 bushels per acre. This field was always flooded in early spring and soil deposited on it. After that initial planting of soybeans that field never produced the plant size or yield of that first bean planting.

    Maybe along with virgin soil research we should get back to longer rotations. One of the rotations being a year of rest for the soil and the micro organisms it contains. Can you imagine a farmer these days setting fallow acreage aside in a rotation? All life has to rest. It just makes common sense to me.

  3. Not really on topic folks but i saw an article today that farmers are having problems with corn rootworm even with GMO corn (designed to counter rootworm) and are being urged to plant less of it in order to “preserve” its effectiveness. The irony of the situation was apparently lost on the author who just reported the issue. I can only shake my head in wonder.
    As always good article Gene. This would be important research but since it would likely gore some precious oxen funding won’t be available.

  4. Gene, not only am I a serious home gardener, I also am a soil-builder, considering this as important as putting food on my familys’ table, and taking pride in its’ gradual improvement using methods as natural as I know how.

    One year, on one of my annual trips back to the motherland Ohio to visit the folks, I noticed the much better condition of the farms in and around Holmes County, compared to the surrounding conventional farms.I never fail to visit that area, a favorite destination just south of where I was raised. I noticed how much greener it was, and this during a severe drought. Has to be the constant addition of organic matter in the form of manures, along with the Amish view of husbanding the land as God intends. Simply a revelation that the Big Boys would rather no one takes notice of.

    I am practicing rotations, green manuring, not trying to squeeze every last drop out of production from the soil, rather building reserves of fertility. This is as important and as satisfying to me as the superior quality food I grow for my family and a few friends.I feel good about it.

    Steve,
    Boulder Creek, Ca.

  5. There has been studies on forest soil and nutrients, I remember at least one. In that case, the nutrient content of the forest soil was very poor, and it turned out that trees with their long deep roots were the most efficiently adapted plants to make use of that soil. I guess it depends on many factors too, like the ratio of evergreens, if the ground is in a slope, etc.

    Dead leaves and fallen logs make a fine compost, but mostly to the benefit of bacteria, moss and fungi. I have sometimes dug into forest soil and quickly found clay or some irony or sandy soil close to the surface, not the dark soil I was expecting. But the kind of compact soil was perfect in a potting mix, to give some substance to the compost.

  6. Human beings – ever the pattern finders – seem to have difficulty following the data and thereby overlook the patterns on which we should mostly focus. I think this topic of soil health hits that mark on the head. It seems we would rather engineer the solution than be engineered by the solution. Lat year I met a man near Wooster, Ohio who grows nursery trees. He mentioned to me that the area recently cleared of its forest grew the strongest, healthiest trees for many years but not so much anymore. There are many components to soil but one I’ve been increasingly fixated on (thanks to discovering a man named Paul Stamets) is the role mycelium play in creating a healthy soil profile whether in a native forest or a home garden. The forest floor is a natural manure field – things fall, rot, decompose — are the decomposers (fungi, bacteria, etc.) just as important as the decomposition itself?

  7. we have just moved to New England and are trying a “woodlands” farm, growing amongst stumps and the edges of clearings..will let you know how it goes

  8. “… things fall, rot, decompose — are the decomposers (fungi, bacteria, etc.) just as important as the decomposition itself?”

    Yes.

    • Yes of course, how not? Wild, mature-forest soil is the ecosystem’s climax growing medium. Everything that lives in it is a plus, no matter what. It ALL helps. And it’s all in balance: nothing gets out of hand and becomes a ‘pest’.

      The best way for humans to get our livings is to reduce our population to where it was about thirty thousand years ago (don’t worry, we don’t have to do anything; in fact we can’t. Gaia has it in hand, and we shall not be able to say no) and then live like a modern analog of hunter-gatherers. Not an exact reversion, perhaps; but an analog.

      That way, we won’t actually do any soil degradation.

      Until that happy day, there’s — for example — Martin Crawford’s work at the Agroforestry Reseach Trust, in Totnes, Devon, Britain:

  9. Maybe we should just let virgin soil remain “virginal.” If word of its wonders gets out, much of our small remaining areas of it will soon get bought up and turn up at big box garden centers in non-recyclable plastic bags labeled “wonder dirt.”

  10. How much of the wonder of virgin soil has to do with never being drained? I sometimes sound like a broken record about my belief that when we drain our land we also drain many nutrients and other unknown beneficial aspects from our soil.

  11. When I was a kid we used to get ‘Woodpile Dirt” to start things like tomatoes and peppers in the Spring from our old woodpile that had been used for many years,which was also under some apple trees.Those apple trees used to bear like crazy and never had any problems,also in the Summer when we wanted to go fishing no matter how dry of a year it was we could always find Earthworms to fish with there.My observations have been that the trees will pull up minerals from deep in the ground and then deposit them thru the leaves every year slowly building up elements in the soil.Blackberries and all sorts of plants always grow the largest at the edge of the woods of course animals love to hang out at the edge of the woods too so their manure also helps build up the soil there.Open fields especially those that are kept cut short or tilled all the time have very little diversity in the way of plants or animals.I love to leave fields alone for a year or two not cutting or grazing them amazing how good the cows and goats do on them when turned back into them to graze.

  12. Please have a look at http://www.echo.org they have a lot of info on this important subject. It is a apparently a commercial success in Africa.
    This is an excerpt.

    Why Multiply Microbes?
    If you have not read “A Fresh Look at Life below the Surface,” we encourage you to do so. If you do not have EDN 96, you can read it on our website or request a copy. The article explains the importance of the vast but largely unseen web of life that exists in the soil. Multiplying and adding soil microbes to fields or gardens is an attempt to strengthen this Soil Food Web. Within the soil, some microorganisms have ‘good’ effects, some can cause harm, and others do neither, or may help or hinder depending on whether the helpful or harmful bacteria are in the majority. Adding good microorganisms is an attempt to shift the balance so that more soil microbes are beneficial to crop growth.
    Other farming practices can also help strengthen the Soil Food Web. These include reduced tillage, application of organic matter to soil, and use of cover crops. But specifically multiplying microbes and applying them to the soil is sometimes recommended especially for soil that is extremely poor or when a farmer is switching from conventional to organic agriculture.
    Tony Flynn

    • I read somewhere maybe in Acres USA that woods soils contained like 5X more microbes than cultivated field soil.On building soil I usually pick a hill top with the poorest soil I can find to store large round hay bales after about 3 years it’ll be the richest piece of land on the place.The first year almost no rot (lack of microbes in the soil) by the end oft he 3rd year anything rots quickly that comes in contact with the ground there.

  13. Amen again! My soil microbiology experience has led me to realize we need to include virgin ecosystems in our list of precious things. They act as sources of inoculum for the amazing variety of soil microbes that cultivation and BAU farming practices neglect and kill. I think every garden needs a certain number of undisturbed corners and/or brushpiles where we just let decomposition happen. They can go on the balance sheets as investment in the long-term.
    Gene, what’s your favorite strategy for digging burdock roots? Backhoe?

    • Kirk, dynamite dislodges them easily enough, but hard on windows in the vicinity. Funny you should bring this up because in a longer article on virgin soil, for a magazine, I get into burdock as maybe a serious crop. I haven’t tried it, but I understand that stir fried burdock root is pretty good and burdock root tea sells high. Gene

      • Gene, see that Martin Crawford video sequence I posted above. Your information about stir-fry burdock root is right, apparently. After the fruiting has finished for this year in the wild ones growing hereabouts, I’m going to give that a try!

  14. After reading this to my three girls they have decided to do an experiment. They are going to mark off a square somewhere on our land that has never been touched. They are going to plant a bunch of seeds there. They are going to plant the same seeds in our of our garden beds. They are really excited to try this out and see if there is any difference. I have to admit I am very curious also :)

  15. A rather ancient resource on soil fungi is Sir Albert Howard’s ‘ The Soil and Health’ written in 1947. The examples given show that the health of the soil determines the health and productivity of the plants and animals, and ultimately the humans who consume them. He is a real advocate of the use of composts, which is what’s going on in the forest all the time, and very disparaging of the use of commercial fertilizers.

  16. Love all the comments above! I’ve become interested in permaculture myself in the last couple of years and am trying to learn and practice it on my own little farm. I have found very helpful and intriguing two books: Edible Forest Gardens, by Dave Jacke, and The Holistic Orchard, by Michael Phillips. They both write extensively about the interconnectedness of soil, microbes, fungi, plants, animals, beneficial insects, etc. What they say helps make sense of the idea of putting a bucket of forest soil in one’s garden. Lamb’s quarters, by the way, are delicious. I “weed” and freeze these volunteers in my veggie garden in spring until I get tired of doing so. Better than spinach.

  17. Although it’s not virgin soil, apparently raw milk also is quite effective in soil improvement. http://audaryadairy.com/2010/06/raw-milk-and-soil-improvement/
    I follow another blog and the pictures from the folks who have tried it are quite impressive. Increases the brix (sugar content) of the grass as well. I haven’t been able to try it because of hubby’s back surgery and the milk cow darn near dying from anaplasmosis, which means she’s dry at the moment. But it’s on my to-do list for next year!

  18. One of my neighbors has gone to 100% no-till farming and it is amazing how much his soil health has improved.

    • No-till is a great concept–letting the dead plant matter feed the soil. But here in Middle Tennessee it means first killing everything green thing with herbicide (while insects are foraging on the plants and weeds), letting the land lay fallow for a “few” weeks, and then drilling GMO corn seed into the field.

      As a result, I may soon be out of the bee business–they yearly loss of bees to agricultural chemicals is just unsustainable.

      I still think no-till is the answer–but without the chemicals.

  19. About thirty years ago when I bought the back side of a larger farm, it was a recent clearcut forest. This is what I wanted. It was gently sloping and south facing, both beneficial for agricultural production high on the Appalachian plateau. It took five years to slowly remove the impediments to cultivation that were present as stumps, laps, brush, rocks and forest debris. That’s because it was all done by hand and with animal power (draft horses). In the process the land has never been moldboard plowed, just chisel plowed and then seeded to horse pasture mix. Now some three decades later it has been mowed annually and grazed in rotation with cattle and horses, mostly horses. We have drug the pastures with a chain harrow and feed hay on it every winter. The land is incredibly lush and fertile. Having land that was previously and recently forested was important to me. I knew it hadn’t been commercially farmed, plowed with a turning plow or sprayed with herbicides or pesticides. Keeping the soil profile in place was important. This land is highly productive and tolerant of all weather extremes of drought or the current excessive rainfall. It’s simply a matter of keeping the soil alive and knowing that life begets life. Thanks for bringing up considerations not normally made Gene. Best Regards, from a longtime fan – Jason Rutledge

  20. Hi Gene,
    I am experimenting (rather unscientifically, alas) with using composted wood chips for garden soil. I heard about it from a friend, and because the ground where we were going to put our garden on was too rocky to till, we thought we would give it a try.

    The wood chips need to be composted at least one year before use, and they must be the sort of chips an arborist has around–the whole tree, leaves, twigs and branches–shredded up together. Don’t try this with store-bought landscaping wood chips.

    We put them down on the rocky, hilltop clay (burying weeds and grass that had been recently mowed short) about 5 inches thick, maybe more like 6 in places. It ended up sitting for about a month after that because I got very sick.

    I planted cucumbers, yellow french beans, zinnias, collard greens, bok choy, dwarf kale, peas, carrots and melons in my first planting. The melons didn’t come up (too cold yet, I was stupid to have tried that early). Everything else came up and is doing beautifully. Well, the peacocks from the farm down the hill ate the peas, but they were great until that happened.

    I have now added another section to the garden, using the composted wood chips, and in that I planted egg plants, tomatoes, bell and wax peppers, basil, more collards and bok choy, zinnias, nasturtium, squash, and one lonely jalapeno. The Jalepeno looks like crap–I think it may have to do with the loads and loads of rain we have been getting. But everything else is growing exuberantly. I added watermelons and muskmelons after it warmed up and they are growing like crazy and covered in ripening melons. Oh, and strawberries–which are currently on their second crop and quite happy.

    Benefits of using the composted wood chips seem to be: 1) absorbs water well and drains well. Soil stays damp between rains, and doesn’t become waterlogged when it’s downpouring (like today). 2) makes weeding fun. Yes, I said fun (and I am a tired, pregnant woman). Because it is so light and loose, it’s no chore to pull anything up. 3) The plants seem to thrive in it without any additional fertilizer. So do the weeds–but, being easy to dislodge, that’s no bother. And I have noticed a phenomena, the cause of which I am not sure of. The bug pests coming into my garden are eating the weeds instead of my garden plants. I do not know if this is a sign that I disrupted the weeds well enough at a young stage to make them weaker and attractive to pests, or what. I did run a light hoe through the soil when I first saw weeds sprouting, and it dislodged a majority of them.

    The real test will be planting the garden again next year. The person who suggested this method of gardening says to cover the garden with more wood chips to keep weeds down, and that after the initial layer of well-composted chips you can use lighter layers of uncomposted chips which will break down enough over the winter to plant in for spring. We’ll see what happens.

    Melissa

  21. The burdock on my farm would be champions, if there was a championship for such things. I got curious how they tasted, so I spent a day digging up roots this spring. (Used a mattock — dynamite would have been better.) Cooked them and ate them, and now I know why carrots were invented. Wife liked them, though.

    Fun fact: the leftovers in the fridge turned a beautiful emerald green in 24 hours.

  22. Imagine my surprise when I looked out an upstairs window on my parents farm and noticed the field layout from 2 generations ago in the colour of the soil.It only happened once and only lasted for 2 days that spring when i assume conditions were just right but it really brought to life how the different management of each field was evident even after so much time has past.I read an article this past spring about a farmer that had been no-till for 25 years and planted on top of the previous years rows every time.Even though he only grew corn and soybeans and used conventional fertilizers he had some type of soil life in the row area different from the normal that was being studied.The article speculated that other farms could be innoculated with soil from this farm to get the soil life going.

  23. Gene & others, Thoughts on this? Thinking weeds grow there already for a reason, but most just do not know how to use them properly to improve soil. This area is hard gravel, was a parking lot, many so-called weeds there.
    Considering followup with Oats_Buckwheat_Winter Rye rotation to eliminate undesirables later.

    Non-Indigenous Invasive (NOXIOUS) Plant Control [Eradication vs Soil Rehabilitation] Test Site Comparing common existing invasive/spreading plants [Legumes, Herbs, Grass] that already provides known benefit to the environment (Pollinator habitat [Food, Nursery, Shelter])
    Spotted Knapweed Centaurea stoebe L. subsp. micranthos (Syn C. maculosa [+ subsp. micranthos (basionym)], Centairea biebersteinii) Produces its own natural herbicide called “(-) catechin” that eradicates plants around it. Spotted knapweed has twelve different biocontrol agents (insects); Seedhead weevils, root-boring weevils, and seedhead flies are commonly used or released to manage the plant, perhaps the most famous of which is the Cyphocleonus achates, or root boring weevil. Origin: Eurasia ; introduced in 1890’s. [Invasive Plants website: http://www.na.fs.fed.us/fhp/invasive plants, National Invasive Species Information Center
    Caution: Wear long sleeves, pants and gloves, C. stoebe can be a skin irritant to some people.
    A pioneer species found in recently disturbed sites or openings. Once it has become established at a disturbed site, it continues to spread into the surrounding habitat. This species outcompetes natives through at least three methods:
    1. A taproot that sucks up water faster than the root systems of its neighbors, the lateral root system enables RAPID spread in artificial corridors, gravel pits, agricultural field margins and overgrazed pastures.
    2. Quick spread through high seed production and Seeds can REMAIN viable in the soil for 7 years!
    3. Low palatability, less likely to be used as food by herbivores. It is also suspected to be allelopathic, releasing a toxin from its roots“(-) catechin” that stunts the growth of nearby plants of other species. This promotes its domination, reduces plant diversity and limits forage and crop production. As spotted knapweed populations rise and other plant species are excluded, surface runoff and sedimentation often increases!
    4. But some western natives, such as Gaillardia grandiflora and Lupinus sericeus, are resistant to (-) catechin-induced toxicity, apparently resistance is conferred by these plants’ ability to produce oxalate. Furthermore, native grasses grown in conjunction with oxalate-producing plants benefited from presence of oxalate.

    http://en.wikipedia.org/wiki/Centaurea_maculosa

    * * * Local plants appearing to survive on this specific site are; Perforate St John’s Wort Hypericum perfolate, Timothy Phleum pratense, Mentha spp. Numerous LEGUMES; Clover (Trifolium spp), Black medic Medicago lupulina {flowers that can be used to create honey]. * * *
    Native of Europe and Asia it has become a serious problem as it is a highly adaptable plant. It can be found at various elevations, in moist or dry conditions, is shade tolerant but can be commonly found in sunny areas and prefers well drained or gravel/sandy soils. It can be found nearly everywhere!
    Ecological Threat: Especially threatens dry prairie, oak and pine barrens, dunes and sandy ridges.
    Spotted knapweed is poisonous to many other native plants (phytotoxic).
    – Catechin phytotoxic compound inhibits seed germination and growth in making phosphorus more available in certain soils. It leads to cell death of competing plants by acidification of the cytoplasm.
    If it has a preference, it will thrive in sunny, arid conditions in course soil and especially in disturbed areas!
    Control Methods: Mechanical Mowing as needed so plants cannot go to seed. Mowing Concerns! Will adapt to mowing and grow shorter and shorter to bloom at very low heights, which is why this plant can vary in height.
    • Prescribed burning, only very hot burns are effective which may also damage native plants.
    • Early detection and pulling (Very LABOR Intensive!)
    Reproduction is primarily by seed, but can sometimes start shoots from the stout taproot with lateral shoots forming new rosettes near the parent plant. Seeds can remain viable in the soil for 7 years!
    Biocontrol Moths Agapeta zoegana and Metzneria paucipunctella. Weevils Bangasternus fausti, Larinus obtusus, Larinus minutus and Cyphocleonus achates. Fruit fly Chaetorellia acrolophi. . Two species of seed head flies, Urophora affinis and U. quadrifasciata, are well established on spotted knapweed. The larvae of these species reduce seed production by as much as 50% by feeding on spotted knapweed seed heads and causing the plant to form galls. Three moth species (Agapeta zoegana, Pelochrista medullana, and Pterolonche inspersa) and
    a weevil (Cyphocleonus achates) that feed on spotted knapweed roots have also been released.
    Biological control agents may be more effective when combined with other control methods such as herbicides, grazing, and revegetation with desirable, competitive plants (* * *).

  24. Hi Gene!
    I have recently purchased a large plot of land that was a farm back from the 1800s to the early 1970s as near as I can tell. It has been neglicted for the past 30 years and I am currently working on restoring it to a working farm.
    I do have a wood lot area that I do not think has used as agriculture in ages and may fit your definition of virigin soil.
    If you like, will offer up a section, plant a given crop (or three) as a test to compliment your testing.

    • Brian, that is most gracious of you. What we need is a way to compare the plants nutrtionally… how many minereals and vitamins etc. I can’t do that. Then we need to know the history of the place… what may turn out one way for you might turn out another way for me because of something that happened five thousand years ago.. I intend to plant a patch of corn, that being kind of a universal plant in America, no more than a clump of about 30 plants, no cultivation at all, in the woods where it gets only half to three fourths sun.. I already grow the comparison in the field next to the woods. See what happens. Of course next year your weather and mine might be different. Hard to do comparisons. Gene

  25. You are definitely onto something Gene. I do a lot of research around many different topics as I am studying for a PhD (no not a young whippersnapper either) in how to incorporate rural inhabitants views into policies on rural landscapes, which means needing to be up-to-date on the newest research on farming techniques, especially the sort that would support farmers rather than corporate bodies and I am reading a lot about the benefits of trees in row cropping, especially drier areas as mentioned above. Your years of observations show how much knowledge is stored amongst rural inhabitants generally and sadly is overlooked, hopefully here in Latvia we might be able to benefit from some old timers years of observations before it’s too late.

  26. I had this epiphany when we first bought our place about 10 years ago. We had rented a bobcat to put in our drive-way and I just happened to notice along the woods how lush everything was so I instructed my husband to fill the bucket numerous times and dump it on my soon-to-be garden. My garden spot was really mostly clay but that woods soil was friable and so lusciously black. Well, everything I planted really soared, but so did all of the burdock seeds and thistle seeds and nettle seeds that I “planted.” Overtime, we’ve changed where our garden is (not b/c of the woods soil), but I’m still fighting all those weeds in that garden area that is now pasture.

  27. After starting a vegetable garden on pasture that was part of a dairy decades ago I can agree that the initial crops were strong, productive and disease free.

    After then the crops have grown weaker despite application of nutrient rich and/or carbon rich fertilisers or green manure rotations. I recently cleared some new pasture and planted a crop with no fertiliser and they are growing perfectly again.

    I suspect it comes down to the loss of the deeper soil structure. Ploughing seems to destroy this the fastest, but hand cultivating or the absence of deeper rooted plants also does the trick over time it seems.

    The exceptional size of the crops on the virgin soil is indicative of them managing to form a very large root system. At conventional horizontal spacing this indicates they managed to form a very deep root system to support all the top growth.

    Id maybe think of it as an equilibrium. Crops are selected so that they take out as much as possible from the soil, so they take as much as they can each year until there isn’t much more to give. Adding fertiliser shifts this equilibrium back to something acceptable, but the problem is we can only apply it to the surface, and at too high a concentration there it is damaging. Virgin soil has stored and available nutrients to a much deeper depth, accumulated by wild plants over time. Crops can take this away, but cannot replace it, and neither can our deepest ploughs.

    I think another possible issue is nutrient balance. A wild system will gradually accumulate the nutrient balance it needs over time, leeching and extracting to a balance. Adding fertiliser then removing a crop creates an imbalance in at least one nutrient that gets worse and worse each year (partially compensated by doing nutrient status testing continuously, but this is beyond the scope of home gardeners).

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