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arjo_reich

Renovating Lawn - Tamping Soil?

arjo_reich
15 years ago

My "soil", term used loosely here, is pretty much 6-12" of red-clay on top lithic bedrock and as I'm renovating my lawn my plan was to till the living bejesus out of it until it was thoroughly broken up, add about 2 cu. yards of rich organic material and then grade and roll it out to prepare the seedbed.

Recently I read online that grass really doesn't like to grow in overly "soft" soil and that I should rent a tamper to give the lower 3-4" of soil a little compaction after grading and only rough up the last inch or two when preparing the seedbed. Then, after laying the seed, pull out the roller to ensure good contact.

The same was suggested to me by a native of the area because unless you give it some compaction like that you'll have the lumpiest grass in the neighborhood for the next 10 years or so, as it slowly settles into place again.

---

I just thought I'd run the idea past the experts here to see if any of that rang true. If so, I suppose the plan for me will be to till it up this weekend, allow it to rest a week to try to germinate any dormant weed-seeds and then go over it again lightly, next weekend, and tamp it down before getting started on the final preparations for the seedbed.

Comments (14)

  • decklap
    15 years ago
    last modified: 8 years ago

    If you just rent a lawn roller after you seed to make sure you've got good seed/soil contact that should be fine. I can't imagine how tilling your soil would give you lumpy grass.

  • arjo_reich
    Original Author
    15 years ago
    last modified: 8 years ago

    I was just a little worried about hearing/reading the bits about clay soils because my soil is *pure* hard, red clay. Last year, in the backyard, I tried to till up a small garden by hand and I couldn't get more than 2" deep without the aid of a pick-axe...and that was _after_ i had thoroughly soaked the area with the hose a couple hours ago.

  • jeannie7
    15 years ago
    last modified: 8 years ago

    arjo, you've said it yourself, the area that grass is wanted to grow in is clay and once below 2" it is pretty hard.

    With any clay foundation the need is to incorporate some organic material into the area to enable it to retain moisture.
    This is either carried out by injecting it into the soil and mixing by rototiller or by laying it over the area and letting nature take it down.
    I believe, because your lawn is being done over anyway, the rototiller, set on shallow digging, will do sufficiently and then the roller taken over after seeding.
    Consider too using a 'starter' type lawn fertilizer when you apply the seed.

    The adding of organic material should be thought of as a spring ritual for next 4 or 5 years.
    The hope is to build some moisture retention method into the soil and giving it 1/2" to 1" of such organic material will help the seed germinate and helps the present lawn do much better.

    If you are rototilling the overall area and are digging down more than just shallowy, then you might, for this year alone, add more than 1/2"...1"...instead, depending on your budget, think to add 2" of compost/composted cattle (or sheep) manure, some leaf mould, (later on some chewed up leaves in the fall), and possibly some peat moss mixed in well.
    when you work with peat moss, use a wheelbarrow and inject some HOT WATER into it. Peat moss, when confronting cold water, will reject it....it mixes much better, much easier when wetted thoroughly with HOT water.
    Then mix the composted organic matter into it and allowing it to dry before applying it to the area.

    If you prefer, take a fan rake, and thoroughly rake the lawn over removing any dead or loose material. Roacks and other debris, lumps of old soil can be removed and given back afterwards.
    Really give the lawn some elbow grease with the rake....do it first north/south, then go back and do it east/west.
    This opens the soil and lets the organic matter and seed make good contact.
    Rolling it lightly completes the needs.

    The present clay soil has no retentive qualities and even with a hard rain or watering, the ground will just not accept it....and it runs off.

    This is what must change. Adding organic matter into the soil....and doing it for the next 4 or 5 years in early spring, I think you will see a marked improvement.

    If you wish to figure out exactly what amounts of compost or good topsoil you'd have to buy....simply
    measure the length of the area, multiplied by the width of the area...in feet.
    Multiply that by the number of inches depth you wish to lay over the ground.
    Then multiply that figure by .003.

    As an example: a yard is 50 feet wide by 50 feet long.
    That's 2500 square feet.....multiplied by...let's use 2"....
    2500 X 2 - 5000.
    5000 X .003 - 15 cubic yards of soil.

    another: 20 feet wide....30 feet long...600 sq. ft.
    times 2".....1200.....X .003 - 3.6 cubic yards.

    Anything over 3 cubic yards should be thought to be brought to the driveway by truck.....otherwise such amount bought by bag could be most expensive.

    For bagged materials, the label should indicate the volume within the bag (a 18 kg (40 lbs) bag usually equals about 1 cubic foot). Simply divide the total volume of compost required by the volume of the bag to determine how many bags are needed.
    There's 27 cubic feet in a cubic yard.

  • arjo_reich
    Original Author
    15 years ago
    last modified: 8 years ago

    Jeannie,

    thanks for the thorough and sound advice. boy, that sure is a lot more organic material than I had originally thought to use but I'm sure it's the right way to go. I already have at least a cubic yard's worth of finished compost that I made last season - I'd say I have over 3 cu. yrds. but the other two yards are unscreened an contain a LOT of twigs and "rooty" material because I was significantly less selective on the particle size going in to that first batch. Other garden beds will benefit from it, so no worries there.

    The actual size of the front lawn is a little under 1900 sq. ft. so my calculations came out to be around 13.5 cu. yrds of material - which is still about 2.5 truckload of material from the local mulch stop - or about $350 USD worth at today's going rate.

    Still, I'm also hoping to reduce that number by thoroughly tilling the existing lawn into the soil. I've been spraying it for the last two weeks on Sunday with round-up and it's almost...finally...completely lifeless.

    Then I'll wait a week and zap whatever's popped up since then with another dose of roundup and get to work on preparing the actual seed-bed - final rolling, grading, etc. type work...

    I've also got it in my mind to put a little one-zoned budget sprinkler system in place while I have everything tilled up - although I might still have to rent a trencher for that :sigh: - simply because it makes sense to do it now and it'll save me the heartache of having to worry about proper watering schedules and equal coverages, lol.

    I have a bag of Scott's Starter Fertilizer and I should have my soil sample results back within a week for any other amendments that might be needed (during that final grading, etc. phase next weekend) as well as a 4lb bag of the powered Tupersan selective pre-emergent herbicide. I figure if between the couple phases of round up, if anything survives I can nail it here when I spray the Tupersan over the Galaxy Plus KBG blend.

    After that, assuming I can locate a rental for a Topsoil Spreader / Compost Roller I planned on putting an even coat of peat moss on top of the fresh seed-bed and using that as my cover - for moisture retention and it's high bioavailability in terms of decomposing.

    ---
    Boy I have to tell you, I seriously feel like I bit off more than I can chew on this one because the process seems to get more and more complex with each day and I'm well past the "put it off until next year" point. :laughs:

  • morpheuspa (6B/7A, E. PA)
    15 years ago
    last modified: 8 years ago

    The adding of organic material should be thought of as a spring ritual for next 4 or 5 years.

    Or shift to an organic feeding method and slowly add it at various points during the year. It's all good and you don't have to make a special trip for organics, or haul all that much at one time.

    You can certainly add something in spring (I used peat moss because that's what I could get) atop the soil, or work it in. That can be in addition to or instead of the organics.

    I had a horrible, solid white clay that was impossible to work. Grass grew, but not well. It had been used as cornfield for forty years, abused, and generally tapped until there was nothing left.

    I'm 2 1/2 years into an organic program and the changes are stellar. The soil is still clay (nothing short of a replacement will change that), but it's now invested with organics. Watering's become rarer, the soil cuts like butter when damp, and the color resembles peat moss.

  • decklap
    15 years ago
    last modified: 8 years ago

    Don't guess at the amount of organic matter you need. Get a test done and it'll tell you exactly what the % of OM is.

    You'll want to see it in the range of 5% or so but lots of people maintain OM at rates like %7 or better.

  • bpgreen
    15 years ago
    last modified: 8 years ago

    I'm wary of tilling a lawn, especially tilling to add organic matter. The problem is that it is then very difficult to get the soil really level and it will settle after you level. This is exacerbated when you add the organic matter, since it will continue to decompose, so places that got more OM will settle more and you end up with a bumpy lawn.

    I would go with a more gradual approach and just top dress the lawn on a regular basis (as morpheus suggests). When I bought my house, the water ran off the clay after a very short time. I toss coffee grounds from Starbucks on the lawn and mulch mow. I also mulch mow my leaves into the lawn and for the past few years, I've been shredding smaller branches from tree trimmings and spreading that around. Just doing those things has changed the soil to the point where I rarely see any run off.

    One more free source of organic matter is tree trimming services. They usually shred the trees as they trim them. They have to haul them to the dump and pay a tipping fee, so if they're in the area and you'll let them dump a load, it saves them time and money. One caveat is that you may need to let them dump the entire truck load at once.

    If you take a more gradual approach, a good rule of thumb is about 1 cu yd per 1000 sq ft per application. If I remember correctly, that ends up being in the neighborhood of 1.4 inch.

  • dchall_san_antonio
    15 years ago
    last modified: 8 years ago

    I always like to ask the question, "What would Mother Nature do if she wanted to plant grass?" The answer to that is NOT to rototill but to place the seed on the surface of the soil and walk on it. She set up the great plains, prairies, savannas, steppes, and other grasslands the same way. Large animals walk in, eat grass, knock seed off the grass as they move through, trample it by walking, fighting, and stampeding, and then let it rain. There are no rototillers in Mother Nature's plan. The best natural analog to the rototiller is the hog, and She did not see fit to cover the world with gigantic herds of hogs. Nor do they dig it incorporate organic material into the soil.

    The reason YOU don't want to rototill is as described by bpgreen. There are other reasons but you are particularly interested in obtaining a level lawn later on. Even if you rototill without organic material, your soil never settles evenly. The soil will be settling for the next three years after being dug or tilled. Tilling in with a mix of compost or other organic material is the absolute worst thing you can do to start a new lawn. I fully agree with your neighbor. And yes, I realize that flies in the face of Sunset Lawn and Garden book as well as all the other books. No respectable professional landscaper would install a lawn with a rototiller. The best ones will use a real tractor (big wheels in the back, small in the front) with a box blade on the back to set your drainage and prepare for sod or seed. The next best will try to use a skid steer or bobcat to do the same thing. These guys will take days to do an hour's worth of work because they are using the wrong tool.

    Your organic matter will increase simply by growing grass. You don't have to do anything except NOT rototill. You can improve the organic material by growing taller grass because tall grass needs longer, deeper roots. More roots in the ground is the definition of more organic matter. Unlike other plants, every year grass sheds its roots and replaces them with new roots. The dead roots become organic matter in your soil.

    If you decide to use compost, and I would discourage it because it is way too expensive for all the benefit you get, use no more than 1 cubic yard per 1,000 square feet. Any more and you will smother your grass and it will die. bpgreen had a typo in his reply: it covers to 1/4 inch, not 1.4 inch. If you use compost, sweep it in with a push broom. That won't break your back like a rake will. Be sure all the grass blades are exposed and all the compost is down into the turf. This rate is a very light dusting. 2 cubic yards is plenty for your small lawn. Compost in my neighborhood costs me $35 per cubic yard and $40 delivery. At 1 cubic yard per 1,000 square feet that amounts to $75 per 1,000 square feet. Whereas if I spread ordinary corn meal or alfalfa pellets (both excellent organic fertilizers) the cost is $6 for 50 pounds which cover 2,500 to 5,000 square feet for a cost of less than $1 per 1,000 square feet. The ground grains have the benefit of being actual fertilizer while compost is not. I'll never buy compost for my lawn again.

    Since you already rounded up your lawn (I wish you had written here first), you have to so something. I would rent a mower and set it to the lowest setting and scalp the current dead grass away. Then seed and roll the seed down to make good contact with the soil. Then water 3x daily for 15 minutes each time for 2 weeks while the grass (and weed) seed sprouts and takes hold. After the grass comes up you can start to back off on the watering. Your only chance of not having a full crabgrass lawn by August is to quickly move to an infrequent watering schedule. Water deeply (at least an hour in each zone) but not very often. Let the surface of the soil dry out between watering. At the hottest part of summer you are shooting for only watering once a week. As for mowing you should mulch mow at the mower's highest setting. This will allow you to have the deepest roots possible. Those deep roots will break up your soil deeper down and you will have soil like morpheusa described. Tall grass and infrequent watering should keep crabgrass out, but if it does not, then be sure to plan to reseed/overseed in the fall. That is the best time to seed because the crabgrass is getting ready to die. It gives your grass all winter to grow roots getting ready for next summer's heat.

  • arjo_reich
    Original Author
    15 years ago
    last modified: 8 years ago

    In regards to the overseeding approach, I was under the impression that I could not overseed my front lawn because it was so poorly managed up to this point - when I bought the house. In my meager 1900 sq. ft. front lawn I have swaths of bermuda, centipede, fescue, quackgrass, KBG, thistle and a vast majority of some kind of red-clover looking weed that roundup is proving fairly ineffective against.

    As I currently do not have any topsoil and do not plan on being in this house for more than the next 3-4 years, tops, I can't really take the 5-6 year topdressing soil amendment approach. My house is losing value by way of about 2% each year just because of my fine choice in neighborhoods for this starter home and I'm just trying to...

    1. stem the tide of depreciation by adding a little extra curbside appeal
    2. create a soil soft enough that when my 9mos son falls on my lawn he only gets a grass stain and not a grass stain with a busted kneecap - as you would if you fell on my grass today.

    I don't have access to a tractor or a box-blade, nor do I think the tractor would be able to maneuver very well between the houses on the small lot size so I figured a tiller set on shallow would be good enough. Especially considering, box-blade or tiller alike will have to go over the soil at least 15-30 times before the chunks of are small enough to actually be considered "soil".

    I hope I don't come across as defensive regarding the advice, although i do get the distinct "bah, you've already screwed it all up" feeling from some of the posts, it's just a little overwhelming with all the conflicting advice, lol. At this point, I'm almost willing to say "screw it", throw one more dose of round-up and don't plant any seed at all and let erosion take care of the problem for me. I wouldn't be the only one in my godforsaken neighbor with a "swept lawn" after last years drought.

  • decklap
    15 years ago
    last modified: 8 years ago

    "Your organic matter will increase simply by growing grass. You don't have to do anything except NOT rototill. You can improve the organic material by growing taller grass because tall grass needs longer, deeper roots. More roots in the ground is the definition of more organic matter. Unlike other plants, every year grass sheds its roots and replaces them with new roots. The dead roots become organic matter in your soil. "

    Dchall have you done any testing to measure the rate of OM increase your getting this way compared to top dressing??

    On a poor soil it seems like this kind of approach would take a looooonnnng time to see any improvment. Its not like there is a wrong way or a right way really, only degrees of benefit, but if the original poster is starting from scratch anyway I don't think compost is a bad option at all.

  • arjo_reich
    Original Author
    15 years ago
    last modified: 8 years ago

    In regards to the current amount of organic material, as soon as I get the results back from the soil lab I should know the answer precisely. However, I'm guessing it'll be pretty low.

    Below are a couple image links of what a spade-full of my "soil" looks like along with the rough-sketch I did of my front yard so a friend (landscape architect / drainage specialist) can help me plan out my little one-zoned el-cheapo irrigation system.

    {{gwi:82980}}
    {{gwi:82981}}

    lol, as for the image of the dirt, that's as deep as I could dig after jumping (185lbs adult male) on the spade a time or two. :sigh: It could be rock or just harder clay under it, but that's typical of my property.

  • dchall_san_antonio
    15 years ago
    last modified: 8 years ago

    Dchall have you done any testing to measure the rate of OM increase your getting this way compared to top dressing??

    Yeah, sure. You tell me the rate of increase your testing gives with top dressing and I'll tell you the rate of increase my testing gives without top dressing. ;-) ...the point being that nobody outside the academic world tests the rate of increase of organic matter. There are far too many variables to hold anything constant to conduct a proper test.

    I'm going to try to get back to the original issue at hand. I am of the opinion that there is (almost) no soil that cannot be redeemed with an organic program, and most can be redeemed anyway. Just so you know the only soil I consider irredeemable is the boron soils in parts of the western deserts. After reading about soils for years, I should define a term or two. Compaction is not simply hard soil. Any soil that dries out enough will become hard. True compaction has to do with driving all the air out of the soil. The only way to do this is to saturate the soil with water and work it until every air bubble or pocket is burst and the only thing left is soggy mud. Let that dry and you have compacted soil. The only people I know of with that problem on a large scale are livestock producers who cannot pull their animals off the land during severe rain. They end up with entire pastures that are "pugged" by the hoof action of the animals. 99.99% of the people complaining about compacted soil do not have anything to approach that type of problem. What they normally have is soil where the moisture content has varied from one extreme to another, back and forth, and the population of beneficial fungi has suffered. A soil that is rich in beneficial fungi is very soft when moist but it still returns to very firm (hard?) when it dries out. Most people come in with an aerator to punch holes in the soil. This technique has no effect on the fungi. Another technique is to top dress with expensive compost. That can work, but it is very costly in time and money. The reason it can work is the compost will provide a mulch later that keeps sunlight off the soil thus cooling it and helping it to retain more moisture. When the moisture is retained like that, the moisture content does not vary so much and the beneficial fungi have a chance to grow back.

    Here is how I have fixed my lawn when it gets hard even when it is moist. I connect all my soaker hoses to another hose and stretch the soakers out in the lawn in a straight line. When I get to the curb I turn it back and lay it down about 18 inches away from the first run. Then I turn the faucet on to a trickle at the faucet and connect the soakers. Almost no water will leak out of the soaker hoses but if you leave it on, day and night, for a full week, it is enough to raise the moisture level of the lawn under the hose so the fungi will start to grow back. At the end of a week I move the soaker by 18 inches and continue to water until I have covered the entire lawn with this process. Then I repeat the process starting back where I started the first time. I repeat the cycle a full three times. So far that has been all it needed to soften my soil. In the end your soil will act exactly like a sponge. That means when it is dry, it will be very firm. When it is wet it will be very soft. When it is dry and you wet it, the water will roll off at first but then soak in very fast.

    arjo reich, I hope your soil test lab is better than mine. I sent in a bag of my compost made from 90% live oak leaves, 5% horse manure, and 5% banana peels. The results came back saying it was too alkaline and needed organic matter.

    I only have two problems with compost:
    1. Cost
    2. People who think compost is a fertilizer rather than a great source of microbes.

    I used to be in the compost camp - all compost all the time. I believed that my soil did not have all the microbes it needed and that compost would help them to appear. Then I was encouraged to try ordinary corn meal to solve a problem I had with powdery mildew on roses. That worked so well I started to investigate why. That led me to learn about the microbes in the soil, the soil foodweb, and how those microbes were fed. Then I realized that microbes were people too and that corn meal and other ground grains provided them with much needed protein, carbohydrates, vitamins, and minerals. Compost does not provide real food. The real food in compost is long gone having been devoured by the microbes in the pile. When you apply compost, you are applying the remains of the food sources plus all those gazillions of microbes. They still need to eat. So I tried simply applying organic fertilizer (ground grains) and found that, lo and behold, my microbes woke up, my soil softened (marginally), white sandy/limestone soil turned dark brown, and my grass turned the darkest green in the neighborhood. Now I am among the throngs chanting, "you already have the microbes in your soil, just feed them." Now I believe that compost is redundant. The microbes really are there - just feed them with cheap dog food (basically ground grains and protein). I used to think the people telling me I was wasting my money on compost were simply organophobes or shills for Monsanto. I am anything but.

    Here are the basics of lawn care (organic or chemical makes no difference). If you follow these words, you will have a green turf to be proud of. You may not like the mix of grasses, but it will be green and lush looking.

    1. Water deeply and infrequently. Deeply means at least an hour in every zone, all at once. Infrequently means monthly during the cool months and no more than weekly during the hottest part of summer. If your grass looks dry before the month/week is up, water longer next time. Deep watering grows deep, drought resistant roots. Infrequent watering allows the top layer of soil to dry completely which kills off many shallow rooted weeds.

    1. Mulch mow at the highest setting on your mower. Most grasses are the most dense when mowed tall. Bermuda, centipede, and bent grasses are the most dense when mowed at the lowest setting on your mower. Dense grass shades out weeds and uses less water when tall. Dense grass feeds the deep roots you're developing in 1 above.
    1. Fertilize regularly. I fertilize on all the major federal holidays - makes it simple to remember. I use organic fertilizer, but which fertilizer you use is much less important than numbers 1 and 2 above.
  • decklap
    15 years ago
    last modified: 8 years ago

    Wow. You're off the compost bandwagon big time huh?? Sounds like Dr. Ingahm has converted your too. You must not be sending your compost samples to her lab. I've read FAQs you've written for other sites and your attitude towards compost was, shall we say, more charitable.

    Im not questioning your bona fides but Im also not sure I grasp your point so let me toss you a couple of questions......

    "Yeah, sure. You tell me the rate of increase your testing gives with top dressing and I'll tell you the rate of increase my testing gives without top dressing. ;-) ...the point being that nobody outside the academic world tests the rate of increase of organic matter. There are far too many variables to hold anything constant to conduct a proper test."

    True I cannot control for every leaf that falls on a property but I've got several examples of before/after testing I've done for customers that I've top dressed for and in each case I see marked improvements in OM and subsequent turf performance. In these cases we're talking about soils that have had very low OM% for years. So while I'll confess Im not establishing the rate of increase to the third decimal point obviously top dressing when appropriate is the fastest way to improve OM%. Wouldn't you agree?? It has not been my experience that a lawn with low OM can repair itself simply by letting nature take its course unless you broaden your timeline considerably and tolerate a very high level of weeds.

    "Compost does not provide real food. The real food in compost is long gone having been devoured by the microbes in the pile. When you apply compost, you are applying the remains of the food sources plus all those gazillions of microbes. They still need to eat."

    I'd like to hear more of your thoughts about this. Maybe I miss the point you're making but it reads as though you're suggesting that microbial life and compost aren't as symbiotic as most people think. Is it your feeling that compost functions much like the water in compost tea in that its just a delivery system for microbial life?? If Im taking your point then what, in your opinion, is sustaining biology in the soil of landscapes that aren't fertilized?

    Generally though I'd agree that compost is widely misunderstood and over prescribed for lawns. It needn't be an annual event. By the same token most of the money people spend on core aeration and lime is money they should take and throw to the wind for all the benefit its doing. Acidic soil and thatch are the modern day boogey man in lawn care. There are circumstances when its appropriate and beneficial but these lawn services that recommend them as a matter of course are wasting people's money in my opinion.

  • dchall_san_antonio
    15 years ago
    last modified: 8 years ago

    Compost is a microbe delivery system. Yes. I believe it is better in one way than compost tea. The huge advantage of compost tea is cost. Tea costs a few cents per 1,000 square feet to cover and compost costs (me) $75 for the same area. However, compost tea will only support the microbes that will wash off of the compost and will survive being submerged in water for 24 hours. So the dry gives you more variety and the tea gives you much lower cost, if you do it right.

    If you have had a chemical spill or even a prolonged flooding event, then compost is in order to replace the dead fungi and aerobic bacteria.

    On top dressing with compost: If you top dress with compost, one of the accepted side effects is that moisture retention is improved. This is because the surface of the soil is covered and protected from sunlight. Basically it becomes mulch at a very small scale. As soon as the soil's moisture levels even out, the beneficial fungi can reclaim their position in the soil. I am not convinced that the compost delivery system has much more benefit beyond the simple stabilization of moisture. This is where it becomes impossible to hold your controls in an experiment. If you apply the same amount of irrigation to two different plots, one with compost and one without, the improved moisture retention of the composted plot would mean that that plot did not require as much irrigation. So how do you water? Would you water according to the needs of the uncomposted control plot or according to the composted plot? Either choice could be unfair to the other because the assumption that both would need to be watered at the same time is not correct.

    Compost does not provide real food. The typical ingredients of compost are leaves, table scraps, maybe manure, and maybe grass clippings. All of these materials are organic and require microbes and moisture to decompose them. The raw materials, called 'feedstuffs' in the industry, contain carbohydrates, vitamins, minerals, and some protein (mostly from the grass). The decomposition process is a microbial process. As the first tier microbes attack the feedstuffs, they are followed by second tier microbes that decompose the byproducts of the first tier as well as the corpses of the first tier 'crobes. This succession of tiered decomposition continues until the famous soil foodweb is formed inside the compost pile. Assuming the compost pile never loses anything, the end result will be the tiny fragments of the undecomposable original feedstuffs plus the later generations of the microbes. There is no fresh protein left. Any protein that was originally there is tied up in the bodies of those last generations of (hungry) microbes. Certainly this is normal and a good thing, but it is not the same as applying organic fertilizer.

    Regarding sustaining biology in landscapes that are not fertilized: I don't think you can. The microbes need food. Historically they received fresh protein, vitamins, carbohydrates, and minerals from dinosaurs (or other animals) that died and fell on the ground, plants that got trampled to the surface, urine, and animal manure. Those got decomposed by the soil biology and the soil foodweb took it from there. Today we are using ground grains and feathermeal as a source of protein, carbs, etc. Blood meal is too 'hot' a source and feathermeal, while very high in protein, is very slow to decompose. But the grains seem to work just fine. Another possibility for substantial 'feeding' of the microbes comes from those microbes that can accumulate (fix) nitrogen from the atmosphere and replenish nitrogen sources in the soil. Those are usually associated with legumes, so if your crop is not a legume, then you can't count on significant nitrogen input from the air. Some cattle producers are letting their pastures return to nature because nature produces a mix of forage plants that include legumes. Typically these graziers will make other changes that help their situation so you can't just single out allowing the pasture to "go to seed."