EARTHWORM PRIMER

“Biological Agriculture” relies on earthworms and other soil critters to do what plows and synthetic chemicals do in conventional agronomic systems.  Follow the advice below to encourage worm populations in your fields:

–>     There are many species of earthworms around the world.  The most common agricultural species in North America and Europe are the Common Garden Earthworm = Nightcrawler = Lumbricus terrestris, and the Manure Worm = Redworm = Eisenia foetida.  These are the most prevalent species sold by worm hatcheries for fish bait and farming.

–>     Nightcrawlers dig vertical burrows deep into the subsoil.  At night the worms rise to the soil surface to feed = they drag bits and pieces of leaves and other organic matter down into their tunnels.  Walk through a field at night with a flashlight and you will see many earthworms.

–>     Manure worms live close to the soil surface and do not dig vertical burrows.  Redworms are specialized to eat manure and so they are rarely seen except around the base of compost piles or in fields where many animals graze.

–>     31 nightcrawlers or manure worms per ounce; 500 worms per pound; 1,000,000 worms = 2,000 pounds = 1 ton.  1 average earthworm (Lumbricus terrestris) or manure worm (Eisenia foetida) from a commercial hatchery weighs 0.002 pound = 0.032 ounce = 0.9072 gram.

–>     Active, adult earthworms (Lumbricus terrestris) eat their body weight in soil and organic matter daily.  Sluggish worms, immature worms, and worms of other species may eat only 10% to 30% of their body weight each day.  1,000,000 common earthworms per acre (about 23 worms per square foot of topsoil 12 inches deep) = 1 ton of earthworm castings = worm manure DAILY during the growing season.

–>     Usage Note:  1 earthworm cast, 2 earthworm casts, many earthworm castings.

–>     Average daily worm cast is about 0.90 gram although weight of surface casts is considerably greater and varies widely.  Average surface cast weight is approximately 10 to 14 grams or about 0.30 to 0.50 ounce.  Surface worm cast weight ranges up to about 2 ounces in temperate climates and considerably more in tropical areas, depending on worm species, soil type, and available food.  For example, 1 average adult earthworm (2 to 3 years old) living in a bed of compost in a tropical climate can produce 10 pounds = 4.54 kilograms of castings annually ~ 12.4 grams ~ 0.43 ounce of castings daily.

–>     Average surface cast volume is approximately 1 Tablespoon = 15 milliliters (plus or minus 7 milliliters).

— >     Earthworms are most active in early spring and mid fall when weather is cool and moist.  Ideal soil temperature = 65 degrees Fahrenheit.  Earthworms are less active during hot, dry summer months.  Earthworms rise to the surface to feed at night then sound to lower soil depths each morning when temperatures rise.

–>     Do not plow in spring or fall if practical as this kills many worms.  Do not plow, cultivate, or spray in early evening, after dark, or early in the morning as this kills many worms.  The best time to till, cultivate, or spray is in the afternoon when temperatures are highest and worms have retreated to cooler soil depths.

–>     Keep fields planted with cover crops in spring and fall to feed worms.  They need much food at this time.

–>     Don’t leave soil bare over winter.  Protect winter fields with an insulating blanket of crop residues, mulch, or cover crops.  1 or 2 inches of organic matter can double earthworm populations.

–>     Earthworm populations increase in direct proportion to the amount of organic matter on the soil surface = leaves, twigs, straw, et cetera.  More cover = more protection & more food = higher worm populations.  Keep the soil mulched or covered with growing plants at all times.  2 inches of mulch double worm populations compared to cornfields where whole stalks are left on soil surface.

–>     Baby earthworms when they hatch from their cocoons = egg cases are very small, only 1/2 to 3/4 inch long.  Earthworms are extremely vulnerable when first hatched.  Do not plow, cultivate, or spray when worms are hatching.

–>     Earthworms need protein in their diet.  Worm populations double on legume fields compared to grass fields.  Earthworms especially favor clovers, particularly white clover.  Include legumes in field rotations, pastures & hay fields, cover crop mixes, and living mulches.

–>     Earthworms breed and grow very slowly.  Baby worms take 2 to 3 years to mature.  A plentiful, steady food supply is essential to support maximum breeding and population growth.  More organic matter (roots, stems, leaves) = more food = faster population growth = more worms.

–>     Earthworms do not spread rapidly.  A worm colony might spread 3 feet in a year.  That’s as fast as earthworms go.  To “seed” worms drop 6 nightcrawlers every 30 feet then immediately cover with a generous heap of mulch, compost, or manure = whatever worms are used to eating.  It takes at least 10 years for worm colonies spaced 30 feet apart to spread across an acre-sized field.  1 acre = 43,560 square feet = 4,840 square yards ~ 0.404 hectare.

–>     Adult worms are particularly sensitive to dietary changes.  For example, worms raised in hatcheries die if placed in corn fields because they have problems adapting to new, strange foods.

–>     Do not try to seed Manure Worms = Eisenia foetida in crop fields.  The manure worms will die because they are not adapted to this environment.  Use only nightcrawlers = Lumbricus terrestris for agricultural development, mine reclamation, terraforming, reforestation, and similar environmental restoration projects.

–>     If you need to seed worms, talk to the hatchery and ask for their best deal on earthworm cocoons.  Baby worms adapt quickly to any food available.  Mix egg cases gently with screened peat moss, corn meal, sifted compost, or similar carrier then “plant” with a common grain drill.

–>     Switching from conventional tillage to no-till does not happen overnight.  Conversion speed is entirely dependent on earthworm food supplies.  There is no solution for worms’ low natural reproduction rates.  Buying more worms or egg cases won’t make the process go any faster.  You can’t fix this problem by throwing money at it.  Patience is required.  You won’t see substantial improvements in soil structure or fertility until the fourth or fifth year of no-till ~ 2 earthworm generations.  Dramatic differences become smack-upside-the-head obvious by the 7th or 8th year without plows ~ 4 worm generations.  Conversion speed is controlled by how many tons of organic matter are added to each field.  Start looking at crops in terms of their biomass production.  This game is all about weight.  The farmer with the most tons wins!

–>     Tillage kills earthworms.  Loses depend on plow type, tillage depth, and time.  Chisel plows are the most destructive, disk plows slightly less so.  Old fashioned moldboard plows are the least destructive of all conventional tillage implements.  Chisel plows kill 3 times as many earthworms as moldboard plows.

–>     RULE:  Less tillage is better than more tillage.  Shallow tillage is better than deep tillage.  “Warm tillage” (afternoon & summer) is better than “cool tillage” (spring, fall, morning, evening, and night).

–>     Till just enough to get your crop in the ground.  Disturb the soil as little as possible.  All you need is a small hole to set transplants or a narrow slot to sow seeds.  It is rarely necessary to till more than 2 inches deep (unless you are planting potatoes).

–>     No-Till is better than strip till which is better than ridge till which is better than whole surface conventional plowing.

–>     Rear mounted rototillers are ideal tools for shallow tillage.  For example:  Broadcast winter wheat and Dutch White Clover = Trifolium repens into standing weeds or cover crop.  Mow vegetation then rototill only 2 inches deep to get seeds into the ground.  Irrigate to firm seedbed or wait for rain.  Your field will look rough and trashy but the litter is necessary to prevent wind and water erosion.  Some seeds will be buried too deep, others too shallow, but enough will germinate and survive to produce a good crop.  If soil is too wet, omit rototilling.  You will still make a profitable crop.  Small seeds do not absolutely need to buried in earth.  Cut weeds or nurse crop will cover and protect seed.

–>     Earthworms do not “like” to eat maize leaves and they especially dislike whole corn stalks and cobs.  Continuous corn = planting maize in the same field year after year reduces earthworm populations to minimal levels.  For best results use a stalk chopper or forage chopper to shred dead corn plants so they decompose faster.  Plant maize into a living mulch of Red Clover = Trifolium pratense or other nitrogen fixing legume.  Follow corn with fall turnips or other cover crop to feed and protect worms over winter.  Rotate corn with legumes or other broad leaf cover crops.  Do not follow maize with a grass or cereal crop unless also planted with a companion crop of clover or other legume.  Broad ecological diversity favors large earthworms populations.  Translation:  Worms like a varied, balanced diet.

Example:     Plant forage maize at 80,000 to 100,000 seeds per acre to kill weeds.  Flatten with a roller-crimper or cut with a sickle bar mower after 70 days (18 tons biomass) or approximately 110 days (30 tons biomass per acre).  This is called Mulch-In-Place.  Direct seed pumpkins or squash through the corn mulch with a no-till seeder.  At the same time, broadcast Dutch White Clover = Trifolium repens or other low growing legume over field.  Clover fills any gaps in the mulch and provides earthworms with a “balanced diet”.  Result:  95% or better weed control and few insect pests.  Mulch keeps fruits clean so farmer gets premium prices for his pumpkins.

Note:     Mulch-In-Place is used to grow crops without herbicides.  Popular mulch crops include Winter Rye = Cereal Rye = Secale cereale in temperate climates and Sunn Hemp = Crotalaria juncea in tropical and subtropical climates.

–>     Adult earthworms can live 9 or more years in captivity.  How long worms live in the wild is unknown.

–>     Worms constantly maintain their burrows which often extend 5 to 6 feet into the subsoil.  About the diameter of a pencil, worm holes are essential for aeration and drainage of natural soils.  Fields with populations of 1 million earthworms per acre typically contain approximately 900 to 1,200 MILES of tunnels.  These tubes are lined with “earthworm cement”, a natural glue that keeps tunnels open many years after resident earthworms have died.  Plant roots follow earthworm burrows deep into the subsoil where moisture levels are relatively constant.  This is why crops grown in biologically managed fields have considerable drought resistance.  (Crop roots also follow weed roots into the subsoil, especially weeds with deep taproots.  This is why melons grown in weeds make a crop in dry years while clean cultivated vines shrivel and die).

–>     If agricultural wastes are plentiful earthworms can be fed just like crop plants on an irrigation schedule.  Apply weed seed meal, spoiled corn meal, dried brewer’s grains or similar DRY organic “fertilizer” at 2 Tablespoons (1/8th cup) per square foot ~ 1 ounce per square foot ~ 5 pounds per 100 square feet ~ 1 ton (2,000 pounds) per acre.  Apply WET materials like spent brewer’s grains or fresh cow manure at 8 Tablespoons (1/2 cup) per square foot ~ 4 ounces per square foot ~ 25 pounds per 100 square feet ~ 5 tons per acre.  Broadcast worm food on soil surface.  Reapply as needed when food is eaten = no longer visible on soil surface.

–>     Ammonia based nitrogen fertilizers kill earthworms.  The worst form is anhydrous ammonia gas.  Liquid ammonia fertilizers are far less injurious.  Note:  Organic fertilizers can also be lethal.  Excessive amounts of manure lagoon effluent decimate worm populations.  It is good practice to irrigate before applying ammonia or any fertilizer, chemical or organic.  (Irrigation prevents plants from absorbing too much fertilizer at once.  Over-fed plants attract insect pests).

–>     RULE:  Chemical fertilizers (or manure lagoon effluents) are best applied in small amounts throughout the growing season, ideally diluted in irrigation water.  For best results do not apply fertilizers to bare soils; apply nutrients only to growing plants.  Earthworms are quite sensitive to concentrated chemicals, organic or synthetic.

–>     To stabilize ammonia in animal manures mix with 5% phosphate rock powder by weight (100 pounds of phosphate rock per ton = 2,000 pounds of manure).  Store under cover until needed.  Spread or incorporate manure on field then immediately seed with Buckwheat (Fagopyrum esculentum) or other phosphorous absorbing cover crop.  (Mixing phosphate rock with manure greatly increases phosphate availability to crops.  Organic acids in manure make phosphorous soluble).

–>     Concentrated chemical fertilizers (especially nitrogen) decrease soil organic matter and earthworm populations.  Spread supplementary organic matter on fields where chemical nutrients are applied.  Whenever practical use organic fertilizers to encourage earthworm growth.

–>     How Earthworm Populations Vary by Soil Type and Land Use

50,000 worms/acre ~ 1  worm/square foot:  Moldboard Plowed Continuous Corn; Acid Peat Soils.

80,000 worms/acre ~ 2 worms/square foot:  No-Till Continuous Corn with Herbicide.

150,000 worms/acre ~ 3 worms/square foot:  Fine Gravel Soils; Coarse Sandy Soils; Medium & Heavy Clay Soils.

170,000 worms/acre ~ 4 worms/square foot:  Bare Earth Orchards (Conventional Cultivation); Alluvial = Silt Soils; Light Clay Soils; Heavy Loam Soils.

225,000 worms/acre ~ 5 worms/square foot:  Medium Loam Soils; Fine Sandy Soils.

250,000 worms/acre ~ 6 worms/square foot:  Chisel Plowed Corn & Soybeans Rotation; Chisel Plowed Continuous Soybeans; Light Loam Soils.

500,000  worms/acre ~ 12 worms/square foot:  No-Till with Herbicides.

650,000 worms/acre ~ 15 worms/square foot:  Moldboard Plowed Continuous Soybeans.

1,000,000 worms/acre ~ 23 worms/square foot:  Biological No-Till (Rye Mulch-In-Place); Orchards with Mixed Grass & Legume Sod; Undisturbed Tall Grass Prairies & Hay Fields; Natural Alpine Meadows.

1,300,000 worms/acre ~ 30 worms/square foot:  Biological No-Till with Mixed Species Cover Crops; Fields Fallowed 5 Years (Mostly Broad Leaf Weeds).

2 million worms/acre ~ 46 worms/square foot:  Continuous Clover Living Mulch; Organic Gardens; Dairy Pastures; Manure Fertilized Fields (22 Tons per Acre Yearly).

3 million worms/acre ~ 69 worms/square foot:  Year-Round Mulch 8 Inches Thick (Vineyards & Berry Farms); Sheet Composting 12 Inches Thick (Orchards); High Humus Organic Gardens; Raised Beds Filled with Compost, Leaf Mold, or Manure.

4 million worms/acre ~ 92 worms/square foot:  Undisturbed Temperate Deciduous Forests with Deep Leaf Litter; Intensively Grazed Alpine Pastures.

5 million worms/acre ~ 115 worms/square foot:  Temperate Rain Forests in Oregon & Washington.

6 million worms/acre ~ 138 worms/square foot:  Intensive Rotational Grazing Dairy Pastures; Manure Fertilized Fields (44 Tons per Acre Yearly).

7 million worms/acre ~ 161 worms/square foot:  Greenhouse Beds 3 Feet Deep Filled with Composted Manure.

8 million worms/acre ~ 184 worms/square foot:  New Zealand Sheep Pastures (Intensive Rotational Grazing).

Note:     Numbers are approximate.  Expect considerable variation between countries, climatic zones, elevation above sea level, and land management practices.  Earthworms do not thrive in acidic soils, poorly drained soils, rocky or sandy soils, or tight heavy clays.  The most important environmental factor for earthworm survival is ORGANIC MATTER.  Earthworm numbers increase or decrease dramatically depending on the amount of available food.  Highest populations occur on soils where plants grow year-round, and on soils covered with substantial depths of leaf litter or other plant materials.  To estimate worm populations use a tape measure and straight-edged garden spade, dig a 1 cubic foot soil sample, then carefully break apart the soil and tally earthworm numbers.  Multiple samples per acre yield more accurate estimates.

–>     1 million earthworms per acre is the Holy Grail for most farmers.  This goal is unreachable with conventional farming practices.  To increase worm populations on a field-scale basis requires a long-term soil conservation strategy including crop rotations, cover crops, living mulches, and reduced tillage.  Additional measures such as improved drainage (vertical mulching or tile lines), increased aeration (subsoil ripping or keyline plowing), and erosion control (terraces, contour planting and strip cropping) may also be required.  Overriding all is the logistics of food supply = providing sufficient tonnage of organic matter to feed an army of earthworms and other soil critters.  This is rarely accomplished unless the soil is covered with growing plants 365 days each year.

–>     A watershed management plan is recommended as more water = more vegetation = higher earthworm populations.  The goal is to capture and store every drop of rain that falls upon your land.  Passive or active irrigation may be needed to maintain worm populations at desired levels.

–>     Reaching the goal of 2 or 3 million earthworms per acre is nearly impossible without some form of “mixed agriculture” = crops and farm animals.  Animals provide manure needed to feed large numbers of worms.

–>     Cow manure applied at 1 pound per square foot ~ 22 tons = 44,000 pounds per acre yearly is sufficient to maintain populations of 1 million earthworms per acre (on fields where plants are grown year-round = 365 days annually).

–>     Earthworm populations soar when pastures are managed by intensive rotational grazing or mob grazing.  High concentrations of livestock (300 to 1,500 Animal Units per acre per day) deposit vast quantities of manure.  Fresh manure is excellent worm food.  (1 Animal Unit = 1 AU = 1,000 pounds of live animal weight, regardless of species).

–>     The ancient Roman practice of cattle penning relies on earthworms to help restore “tired”, “weak”, or “sick” fields.  Erect temporary fencing around land to be healed.  Broadcast seed or spread wildflower hay over soil.  Fill enclosure with livestock until land is “well crowded” = animals have just enough room to turn around ~ 8 x 8 feet = 64 square feet per cow ~ 680 cows per acre.  Feed livestock in pen until land is “well dunged and trodden” = 1/2 to 1 pound of manure per square foot ~ 10 to 20 tons of manure per acre = move livestock to new pen every day or every other day.  Cattle stomp seed into earth.  Earthworms and dung beetles till soil.  Manure and urine fertilize ground.  Pastures or fields are “enlivened” = revived by intensive dose of organic matter which causes soil critter populations to soar.  Soil organisms jump start biological nutrient recycling system which supports land revegetation.  Earthworms provide natural soil restoration without tractors, diesel fuel, or synthetic chemicals.

–>     Greek philosophers first noted the link between earthworms and improved crop growth.  This observation led to the development of worm farming practiced by cottagers and other small landholders who did not have cows or draft animals to produce manure for fertilizer.  In spring spread cut weeds and other green plant materials over garden.  Apply mulch thickly = 8 inches deep.  This was the original green manure.  In fall, rake tree leaves and spread over garden 8 inches deep.  Keep garden covered with weeds and leaves year-round.

The night before planting, take a lantern and collect earthworms from hay fields or pastures.  Put worms in a pail with damp moss or leaf mold to keep the “wrigglers” from drying out.  Set several worms with each seed or transplant.  cover immediately with soil and just enough mulch to lightly shade the soil.  When plants are established tuck mulch close around their stems.  Water garden as needed.  Do not spade, fork, plow, till, hoe, or cultivate soil — just plant, mulch, and harvest.  Continuous mulch feeds and protects earthworms and topsoil.  You can run entire farms on nothing but fresh cut weeds and native earthworms.  Space rows widely so there are sufficient weeds to mulch crops liberally.

–>     Over a typical 5 to 6 month growing season, 1 million earthworms per acre will excrete 150 to 180 TONS of worm casts.  These are deposited throughout the soil profile from the surface to approximately 6 feet deep.

Note:  This is a vast amount of nutrients ~ 6.88 to 8.26 pounds of earthworm castings per square foot!  Where does all the fertilizer go?  There are far more available nutrients than any crop could possibly absorb.  This is a mystery.  Nutrient recycling must be extremely rapid with most of the fertilizer elements held within soil critters and organic matter.

–>     Fertilizer Analysis of Surface Earthworm Casts Collected Nightly for 31 Days in July 2011 from 16 Organic Farms in Austria:

2.56% Nitrogen : 1.31% Phosphorous : 1.56% Potassium: 3.69% Calcium = 51.2 pounds Nitrogen + 26.2 pounds Phosphorous + 31.2 pounds Potassium + 73.8 pounds Calcium per ton of earthworm casts.  Average organic matter content of earthworm casts sampled = 7.1% by dry weight.  50 casts bulked for each sample.  16 farms x 31 days = 496 samples total.

–>     Average Nutrient Concentration in Earthworm Casts:

5x Nitrogen (500% more N than found in parent soil)

7x Phosphorous (700% more P than found in parent soil)

10x Potassium (1,000% more K than found in parent soil)

1.5x Calcium (150% more Ca than found in parent soil)

3x Magnesium (300% more Mg than found in parent soil)

Earthworms are living fertilizer factories.  They ingest their weight in soil and organic matter daily then excrete manure containing concentrated plant nutrients.  These nutrients are highly available = easily absorbed and will not “burn” plant roots.  Earthworm casts are rich sources of essential plant micro-nutrients.  These trace elements are often “tied up” = unavailable in parent soils but highly soluble in earthworm casts.  Plants fertilized with earthworm casts rarely require additional nutrients.  This is why earthworm casts have been the standard natural greenhouse fertilizer since the 17th century.

Would You Like To Know More?     Contact the Author directly if you have any questions or need additional information about managing agricultural earthworm populations.

Please visit:     http://www.worldagriculturesolutions.com  — or —  send your questions to:  Eric Koperek, Editor, World Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 United States of America  — or —  send an e-mail to:  Eric Koperek = worldagriculturesolutions@gmail.com

About The Author:     Mr. Koperek is a plant breeder who farms in Pennsylvania during summer and Florida over winter.  (Growing 2 generations yearly speeds development of new crop varieties).

 

 

 

 

 

 

 

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CROPS AMONG THE WEEDS

As I sit here at my drafting table, the local code enforcement officer is looking askance at my “lawn” which is not mowed at the regulation height of 6 inches or less.  Instead, I have 2 research plots in front of my office, both planted with Peruvian land race potatoes.  One plot is mulched with stable bedding, the other plot covered with weeds up to 4 feet high.  The mulched potatoes are riddled with flea beetles; there are so many holes that the leaves look like window screening.  3 feet away, potatoes growing in weeds have only a few scattered holes in their leaves.  These results are typical of crops grown au naturel = in the wild.

When I was young, “good” farmers were judged by the straightness of their furrows and the cleanliness of their fields.  Bare earth and weed-free crops were the standard of good agricultural practice at that time.  Contrarian that I am, my fields were always less than pristine.  Many decades later, my crops are still a herbicide salesman’s nightmare.  The reason is that I have long since stopped trying to eradicate weeds.  Now, I manage them.  I encourage them.  I even plant weeds because I never seem to have enough wild plants in my fields.

Am I daft?  Certainly.  I am also wealthy because I don’t have big pesticide bills to pay.  My crops may not make record yields, but I am not aiming for a blue ribbon at the County Fair.  I measure success on the bottom line.  Who wants to spend $2,000 to plant a half acre of peppers?  I gladly trade low production costs over huge input bills.  I make more money by saving money.  As an added benefit, my customers can pick vegetables without worrying about being poisoned by agricultural chemicals.  I don’t need “organic” certification.  My customers pay me not to spray.  That’s good business any way you figure it.

Down the road I have a wilderness of citrus interspersed with live oaks, Spanish moss, and pangola grass.  It’s an old orchard that is long overdue for rotation, but it still makes me money because I spend almost nothing to maintain the trees.  Every now and then I spread some racetrack manure.  The irrigation system turns itself on and off.  The weeds grow 6 feet high.  Once a year, right before harvest, I mow between the trees — just enough so folks can pick the fruit.  Result:  No bugs on my trees.  Across the hedgerow of old-fashioned hibiscus, my neighbor clean cultivates his orchard and sprays with robotic frequency.  Every spider mite in the district comes to eat his leaves.  Chemical companies use his orchard to test new pesticides.  The mites don’t seem to mind; they eat insecticide like salad dressing.

Up the road are stake-less tomatoes (with thick, upright stems) transplanted into Berseem = Egyptian clover (Trifolium alexandrinum).  I used to walk the fields pulling any weed not blotted out by the clover.  Now, I don’t bother.  I let the weeds grow wild.  Occasionally, I thin the weeds if they grow too thick.  My fields look messy but I rarely see a hornworm.

Across the lane is my pride and joy: A jungle of weeds and melons.  The weeds grow over my head and the melons grow over the weeds.  The trick is to mulch the young melons (or mow the weeds) just until the vines start to run.  After the melons are well established, the crop fends for itself.  Vine crops thrive in the light shade cast by nearby weeds; the best fruits come from the weediest parts of the field.  Insect pests don’t like the broadleaf jungle so I never have to spray vine crops grown in weeds.

Intelligent Weed Management

Tired of getting sick every time you spray a field?  Use the following rules-of-thumb to create a healthy cropping system tailored to your local soil and climate:

>>>  Weeds are a type of living mulch:  Plants grown to reduce soil erosion, enhance soil fertility, attract beneficial insects, and help retain soil moisture.  Before planting into weeds or any other living mulch, remember that two crops are growing on the same land at the same time — the mulch crop and a cash crop.  Success requires careful management or both crops may fail.

>>>  All living mulches compete with their companion crops.  The extent of competition and consequential yield loss vary with management and crop type.  For example, under drought conditions shallow rooted crops generally show more yield loss than deep rooted crops.  Low or slow growing crops many be overwhelmed by more aggressive companion crops.  As a general rule, living mulches are not recommended where drought is expected because yield losses are too high.  However, many crops benefit from living mulches during dry conditions — the companion plants shade the soil, retard evaporation, and increase humidity.

>>>  Weeds make good living mulches for transplanted vegetable crops provided:  (1)  Crops are irrigated,  (2)  Crops are fertilized, and  (3)  Crops are protected for the first 4 to 6 weeks from competition by the weeds.

>>>  1 to 2 inches of water are needed weekly to grow both weeds and vegetables without undue competition for moisture.  If water is limiting, it is best to drip irrigate the cash crop rather than water the entire field.

>>>  Weeds grow quickly so there is often intense competition for light when cash crops are young.  Mow or roll a narrow strip where transplants will be set, or apply a circle of mulch around transplants to give crops a head start.  Once crops are well established they will usually hold their own.  If necessary, prune or thin weeds to increase light penetration for cash crops.

>>>  Roller-crimpers are better than mowers for weed management.  Mowing stimulates plant regrowth; crimping does not.

>>>  Aggressive, fast-growing crops like tomatoes, peppers, okra, melons, squash, sweet potatoes, gourds and pumpkins all do exceptionally well when transplanted into weeds.  Cucumbers are slower growing and require extra mulch to protect them from early season competition with weedy nurse crops.

>>>  As a general rule, broadleaf weeds make better nurse crops than wild grasses which are more competitive and difficult to manage.  Where weedy grasses are a problem, burn the fields or treat with organic herbicide before transplanting cash crops.

>>>  It is good practice to leave strips of meadow, weeds, wildflowers, cover crops, or other living vegetation between or around fields of cash crops.  These buffer strips act as refuges for beneficial insects needed to control crop pests.  The best refuge plants have small flowers so that good bugs can easily obtain pollen and nectar.  Examples include buckwheat, turnip, rape, clover, and any member of the botanical family Apiaceae = Umbelliferae = carrot family = Anise, Dill, Angelica, Chervil, Celery, Caraway, Coriander, Cumin, Carrot, Fennel, Lovage, Parsnip, and Parsley.

>>>  As a general rule, it is unwise to harvest fields all at once.  Divide fields into strips or parcels then harvest each sequentially.  Leaving un-harvested areas allows predatory insects to migrate from disturbed spaces.  The idea is to preserve a balance between predator and prey to prevent sudden population crashes.  Translation:  You want a resident population of good bugs waiting to eat any bad bugs that fly into your fields.

>>>  If weedy fields are unavailable for planting, seed conventional cover crops.  The best living mulches are low-growing, nitrogen fixing legumes like Dutch White Clover (Trifolium repens), Crimson Clover (Trifolium incarnatum), and Red Clover (Trifolium pratense).  Remember to inoculate legume seeds with compatible nitrogen-fixing rhizobium bacteria.

>>>  Where land is weak or vegetation sparse, plant weeds to restore soil health.  Spread weedy hay over sick fields.  Seed wildflowers adapted to your local climate.  Broadcast grain elevator screenings liberally; screenings are dirt cheap (often free) and contain many weed seeds.  If necessary, seed a nurse crop of common rye (Secale cereale) or millet (Panicum miliaceum) to help establish a vigorous weed population.

>>>  Where agriculture is problematic (bare soils, unfavorable climate, no water or fertilizer) it is best to seed mixed cover crops to mimic the diversity of naturally weedy fields.  Choose 2 cool season grasses + 2 cool season broadleaf plants + 2 cool season legumes + 2 warm season grasses + 2 warm season broadleaf plants + 2 warm season legumes.  Include 2 root crops (forage radish, turnip, or stock beet) to help break up compacted soil layers.  Total:  14 different cover crop species.  Plant at least 20 pounds of mixed cover crop seed per acre = 23 kilograms per hectare.

>>>  Weeds are nature’s band-aid; they are specifically evolved to rapidly cover disturbed soils.  Tillage encourages weed germination and stimulates weed growth.  Consequently, to manage weed populations avoid tillage whenever practical.

>>>  It is best not to disturb healthy populations of weeds or cover crops once they are well established.  Broadcast, transplant, or drill cash crops into surface vegetation.  Use equipment specifically designed for no-till planting on trashy, high-residue fields.  For surface (broadcast) planting, increase seeding rates to maximum levels or use clay pelletized seed.  (Pelleted seeds greatly increase plant survival).

>>>  Weeds are most efficiently controlled by using the natural competitive abilities of crop plants.  For example, top seed forage radish (Raphaus sativus variety longipinnatus) over oats when they start to head out.  The radish understory crop grows slowly until grain harvest.  After oats are combined, radish growth explodes quickly covering the field and blotting out nearly all competing plants.  Weeds never have a chance to get established.  Top seeding into standing vegetation is a great way to grow small-seeded crops without using herbicides.

>>>  Grind weed seeds into flour and use like cotton seed meal as a cheap, slow-release organic fertilizer.  1 ton of weed seed meal supplies approximately 54 pounds of nitrogen, 18 pounds of phosphorous, and 18 pounds of potassium (2.7% nitrogen, 0.9% phosphorous, and 0.9% potassium by weight).  Note:  There is no standard analysis for weed seed meal.  NPK values vary depending on the mixture of species in local samples.

>>>  Every farm has different soil and micro-climate.  Agronomic practices that work in one field may fail in another.  For best results, every farmer should maintain one or more research plots so that new methods can be tested and adapted to local conditions.

>>>  Effective weed management requires careful observation and close attention to detail.  Every farmer must become a weed biologist.  Timing of field operations is critically important.  Planting 2 weeks earlier or later can result in stunning success or dismal failure.  Continuous experimentation  is needed to develop weed control programs for each individual crop, field, and farm.

Organic No-Till Weed Control

Conventional no-till agriculture relies on synthetic herbicides to control weeds.  Following no-till method uses an all-natural herbicide substitute made from acetic acid (vinegar) and citric acid (lemon juice).  Combination makes a non-selective vegicide that works like Roundup (glyphosate) to kill both grasses and broadleaf weeds.

Organic Herbicide Formula By Weight For Farming

10%          Glacial Acetic Acid (liquid)               100 grams

5%            Citric Acid (powder)                         50 grams

83%          Water                                                 830 grams

2%            Wetting Agent (surfactant)            20 grams

100%       TOTAL PARTS BY WEIGHT        1,000 grams

This is a non-selective herbicide = kills everything.  Wetting agent is essential for herbicide to stick to leaves.  For best results, apply herbicide on a warm, sunny day when weed leaves are dry.  Herbicide works best on annual broadleaf weeds and grasses 6 inches or less in height.  This is a burn down herbicide; only surface vegetation is killed.  Herbicide will not kill perennial weeds with deep taproots or grasses with growing points below soil surface.  Herbicide is not translocated to roots or other plant parts.  Weeds die from water loss through their leaves.  Caution:  Glacial acetic acid (industrial strength vinegar) is strongly corrosive.  Protect skin and eyes from acid.  Wear gloves and goggles when mixing and spraying herbicide.  Rinse with pure water if necessary.

Organic Herbicide Formula By Volume For Gardening

This formula uses common vinegar (5% acetic acid) and bottled lemon juice (3% to 8% citric acid) that can be purchased from neighborhood grocery stores.

1,250 milliliters          Common White Vinegar          5 Cups

250 milliliters            Bottled Lemon Juice                 1 Cup

30 milliliters              Dish Washing Detergent          2 Tablespoons

1,530 milliliters        TOTAL VOLUME                     6 1/8 Cups

Above concentration will kill annual broadleaf weeds and grasses 6 inches or less in height.  For best results apply herbicide on a warm, sunny day when weed leaves are dry.

Organic No-Till Procedure

This technique works best with small grains, turnips, and other crops that can be broadcast rather than drilled.

(1)  Select ground with good weed or crop cover.  Weeds or nurse crop will be used as mulch to protect germinating cash crop.  (2)  Broadcast seed into standing weeds or cover crop.  (3)  Kill weeds or nurse crop with organic herbicide.  (4)  Mow weeds or nurse crop when dead.  (5)  If desired, top seed established crop plants with Dutch White Clover (Trifolium repens), Red Clover (Trifolium pratense), Crimson Clover (Trifolium pratense),  or other low growing legume.

Mulch-In-Place

>>>  It is impractical to mulch large fields by hand because the volumes required are too large.  The solution is to grow a mulch crop then kill it by mowing, crimping, or spraying with herbicide.  Seeds or transplants are then set through the surface mulch.

>>>  8,000 to 10,000 pounds of straw mulch per acre are needed to achieve 90% weed control.  A crop of rye grain (Secale cereale) 5 to 6 feet high normally yields 4 to 5 tons of biomass per acre.  Most mulch-in-place systems use grass crops because cereal straw decomposes slowly.  Broadleaf cover crops rot faster leaving holes in the mulch through which weeds grow.

>>>  Mowed fields are best transplanted by hand because no-till planters often get clogged by loose plant materials.  Sickle-bar mowers are better than rotary or flail mowers because they do not chop or scatter the mulch.  Good weed control requires a dense layer of long straw which blocks sunlight and acts as a physical barrier to weed emergence.

>>>  Rolling down a cover crop is faster than mowing.  Roller-crimpers are cheaper than mowers and cost less to operate.

>>>  Roller-crimped fields are ideal for no-till seeders and transplanters.  Always work “with the grain” = in the same direction as the cover crop or weeds are rolled.  Never work against or across the grain or surface mulch will clog planting machinery.

>>>  Mulch crops are best killed when in full flower or early seed set.  Earlier harvest reduces mulch yields and increases chances of regrowth.  (You do not want the cover crop competing with the cash crop).  Late harvest risks reseeding by the mulch crop.  (Seed carryover between seasons turns a good mulch crop into a bad weed problem).  For example:  The best time to kill cereal rye is when the seeds are in their milk or soft dough stage.  Harvest at this time guarantees maximum straw yield and zero regrowth.

>>>  It is good practice to top seed a low growing legume like Dutch White Clover (Trifolium repens) immediately after seeding or transplanting cash crops.  Clover plants fill any holes in the mulch and increase biodiversity in the field.

>>>  To make your own roller-crimper, start with a steel cylinder 12 to 24 inches diameter, like a lawn roller.  The cylinder can be any convenient length; 8 to 10 feet long is the smallest roller recommended for efficient commercial farming.  Weld dull blades of 1/4 inch steel to the roller.  Each blade should be 4 to 5 inches high.  Space blades 7 to 8 inches apart.  Angle blades across the cylinder in a wide V-shape like a chevron; this prevents roller from bouncing around and greatly improves crimping effectiveness.  Mount roller on frame attaching to a 3-point hydraulic hitch on tractor front.  When finished, roller and frame should weigh 3,000 pounds; this weight is necessary to thoroughly crimp mulch plants so they do not regrow.  If desired, roller can be designed to hold water ballast so that weight can be increased for tough-stalked mulch crops like forage maize.  Detailed plans for roller-crimpers are available from the Rodale Institute = http://www.rodaleinstitute.org

Medieval No-Till

Plowing in the Middle Ages was hard, slow work.  Heavy wood plows were ponderous, inefficient, and difficult to turn.  A man with a team of 2 oxen took 3 whole days to plow and harrow a small 1-acre field just 22 yards wide x 220 yards long.  The alternative was even worse:  Digging by hand was back-breaking labor requiring at least 30 days to till 1 acre with spade or fork.  It did not take long for farmers to figure out easier ways to grow crops.  The Dutch were the first to apply the new agricultural technology which married free-range pig ranching with a clover-wheat-turnips rotation:

In spring, fence off plot of Dutch White Clover (Trifolium repens) and turn in swine.  (Pigs like Dutch clover because it is sweet.  Do not put rings in hogs’ snouts or they will not be able to root).  Pigs “plow” soil like a rototiller, uprooting all vegetation.  Broadcast spring wheat onto pig-tilled earth then drive sheep back and forth across land.  Sheep stomp wheat seeds into ground.  When wheat starts heading out (or at least 2 weeks before harvest) broadcast turnip seed over standing grain.  After wheat is cut, fast-growing turnip leaves carpet field overwhelming competing plants.  About 2 weeks before turnip harvest broadcast clover seed over standing foliage.  When roots are lifted, young clover plants blanket field, blotting out most weeds.  Clover cover crop protects and fertilizes soil until following spring when rotation cycle is repeated.

On a typical farm in northern France or upstate New York, no-till clover-wheat-turnips reliably yields 40 bushels of wheat per acre (2,400 pounds per acre = 2,694 kilograms per hectare) without hybrid varieties, irrigation, tractors, diesel fuel, chemical fertilizers, synthetic herbicides, insecticides or fungicides.  (Note:  This rotation works equally well with Oats = Avena sativa, Barley = Hordeum vulgare, Rye = Secale cereale, or Millet = Panicum miliaceum).

Sow-And-Go

No-Till agronomy is not a new idea; no-till was practiced in the Middle Ages (and probably earlier).  Then, no-till was used mostly by small farmers who did not own draft animals — or — as an emergency measure practiced only when primary crops failed or when an army swept through the district (stealing all of the food and farm animals).  Medieval records indicate that no-till was a desperation technology often used by peasants to prevent starvation:

Foul weather prevailed through spring.  Fields could not be plowed so farmers sowed in the rain, scything weeds to hide the seed from birds and mice.  By Divine Grace a crop was made, only two thirds of normal harvest but sufficient to forestall general famine among the tenants.  Tithes were not collected this autumn and the Church distributed alms and acorns to the poor.  Annals of the Abbey of Saint Marien [Lake Constance, Germany] Anno Domini 1340

How To Do It:  Find the weediest field possible.  Broadleaf weeds are best and thistles best of all.  (Thistles indicate fertile soil).  Broadcast seed directly into standing weeds.  (Pelleted seed greatly increases seedling survival, especially for large-seeded crops like peas and beans).  Mow down weeds with a scythe (or use a lot of people with sickles or machetes).  Cut weeds act as mulch for germinating crop.  Pray for rain.  Come back at harvest time and hope for the best.  Yields are low but surprisingly economic (because there are no costs other than seeding and harvest).

Medieval No-Till Yields of Dry Peas:  Poor Crop:  4 to 5 bushels = 250 to 300 pounds per acre.  Average Crop:  6 to 8 bushels = 400 to 500 pounds per acre.  Good Crop:  10 to 13 bushels = 600 to 800 pounds per acre.

Medieval No-Till Yields of Spring Wheat:  Poor Crop:  4 to 6 bushels = 275 to 400 pounds per acre.  Average Crop:  7 to 10 bushels = 440 to 650 pounds per acre.  Good Crop:  11 to 17 bushels = 660 to 1,040 pounds per acre.

Sow-and-Go planting is ancient technology adapted for modern machinery.  In India it is called Zero Budget Natural Farming.  Australians use the term No-Kill Cropping.  Some call it Do Nothing Farming, Zero Petroleum Agriculture, or Minimum Effort Agronomy.  Less charitable souls use the term Subsistence Agriculture.  Regardless of label, the principle remains identical:  Sow seed (without tillage or any other investment) then forget about the crop until harvest time.  Small fields are hand planted, large areas seeded with no-till drills.  The trick is to sow when plants normally drop their seeds, usually during the dry or cold season when weeds are dead or dormant.  Native vegetation is left standing; this is necessary to prevent erosion, feed soil organisms, aid water infiltration, slow wind speed, provide shade, increase humidity, improve biodiversity, and trap snow.

Sow-and-Go agronomy is particularly suited where climate or soils are problematic, especially drought-prone, semi-arid regions like Australia and the western prairies of North America.  Old farms, hay fields, pastures, range lands, or any relatively flat area of grass or weeds is suitable for Sow-and-Go planting.  For best results, no-till planters should have razor sharp coulters to slice through surface vegetation, chisel tines or cultivator shoes to open a narrow slot for seeding, and double press wheels to ensure good seed to soil contact.  Minimal soil disturbance is essential for success.  Pelleted seeds are recommended for broadcast planting or land restoration.

In years with good rainfall, Sow-and-Go crops typically yield 60% to 70% of conventionally grown plants.  Translation:  Expect 40% yield losses compared to full-tillage or herbicide treated crops.  Higher yields are sometimes possible on particularly deep or fertile soils.  Drilled crops generally yield more than broadcast seeded crops, especially when seeds are large, weather is dry, or when planting naked seeds.

Sow-and-Go cereal culture is the wave of the future.  Farmers should set aside a few acres to test this new biological technology which can be used to grow any kind of small grain including pseudo-cereals like amaranth (Amaranthus caudatus), buckwheat (Fagopyrum esculentum), and quinoa (Chenopodium quinoa).  If weedy fields are not available, seed mixed cover crops of annuals or perennials then plant into this artificial prairie.  Soil fertility and structure improve rapidly under continuous vegetation, especially if legumes and root crops are included in the mix.  Each year planting becomes easier and yield potential increases.  Results are often surprising and cannot be easily predicted because of complex interactions between many species in a new, “designer ecology”.  Careful observation, precise timing, and constant adjustment are needed to “tweak” the system to favor particular crops.  Real ecological management is required — the very opposite of robotic, spray-by-calendar conventional agriculture.  Sow-and-Go farmers are never bored; they are always making new discoveries in their fields.

Related Publications

Managing Weeds as Cover Crops; Weed Seed Meal Fertilizer; Trash Farming; No-Till Hungarian Stock Squash; Planting Maize with Living Mulches; Organic Herbicides; Pelleted Seed Primer; Living Mulches for Weed Control; Forage Maize for Soil Improvement; Forage Radish Primer; and Rototiller Primer.

For More Information

Readers who have any questions or require additional information about growing crops in weeds should contact the Author directly:

Please visit:  http://www.worldagriculturesolutions.com  — or —  send your questions to:  Eric Koperek, Editor, World Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 United States of America  — or —  send an e-mail to Eric Koperek = worldagriculturesolutions@gmail.com

About The Author

Mr. Koperek is a plant breeder who farms in Pennsylvania during summer and Florida over winter.  (Growing 2 generations yearly speeds development of new crop varieties).