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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THE EDGE EFFECT

What Is It?     All chemical reactions take place on surfaces.  The more surface area, the more reactions take place.  The biological corollary to this natural law is called the edge effect:  Life increases proportionately to the boundary area between different environments.  More edges = more interaction between environments = more food and habitat = more varied species and larger populations.

For example, where cold ocean currents meet warm currents there is an explosion of life along the boundary layers between uniquely different ecologies.  Plankton and bait fish thrive.  Abundant food supplies support large populations of predatory fish which, in turn, attract apex predators like man.  Fishing boats congregate in the whorls formed by mixing currents.  More edges = more life.

Life Breeds Life:     Every time a new species is added to an environment it provides food and habitat for numerous other species.  As species diversity increases the local ecology becomes more complex, more stable, and more capable of supporting additional life.  In short, life breeds life.

Practical Farm Ecology:     Farming is a type of ecological management; each field, pasture, and hedgerow is a different environment with its own varied species and micro-climate.  Smart farmers manipulate agricultural ecologies to achieve specific ends such as pest suppression, erosion prevention, soil development, water conservation, pollution control, and climate moderation.

How To Do It:     The basic principle is simple — create as many edges as possible across the land.  Establish or encourage as many species as practical.  Follow the examples below and watch life flourish on your farm.

Pests Be Gone:     Many modern farmers plant fence row to fence row then tear out the fence rows to make even larger fields.  Wrong.  Huge fields = fewer edges = more pests.  A better strategy is to divide large fields into smaller units — or — plant dissimilar crops in long, narrow strips within each field.  Alternate tall crops with short crops, narrow-leaved crops with broadleaf crops, nitrogen-fixing crops with non-legumes.  Every field should have at least 2 unrelated species.  For example, plant narrow 4-row strips of corn and soybeans rather than vast monocultures.  Result:  Pest populations drop 50% and corn yields rise 15% (because leaves get more sunlight).

Medieval Ecology:     Back when knights went clanking around in armor, farmers grew crops in long narrow fields (because it was difficult to turn heavy wood plows).  A typical 1-acre field measured 22 yards wide and 220 yards long.  Adjacent fields were planted with different crops, forage plants, or fallow.  This strip cropping system created many edges = large populations of beneficial insects.  Medieval records rarely mention plant pests because the good bugs ate the bad bugs.  No synthetic chemicals necessary.

Head Rows:     Tractors and horse teams need lots of space to turn around; turning areas at field ends are called head rows.  On most farms head rows are left in sod or, even worse, bare earth.  Head rows are one of many unique farm environments and should be managed accordingly.  There are far better and more profitable alternatives to common grass or naked ground:

(1)  Expand head rows to enclose each field.  This enables farm equipment to circle around crop margins, increasing mechanical efficiency and creating more edges.  Result:  Instead of having two isolated head rows, you now have two fields, one larger field inside a smaller border field.

(2)  Plant the surrounding buffer field with quick-growing cash crops like buckwheat (Fagopyrum esculentum), bee plants like lacy phacelia (Phacelia tanacetifolia), or seed with mixed forages and clovers, wild flowers, or specialty seed crops like anise (Pimpinella anisum), dill (Anethum graveolens), caraway (Carum carvi), coriander (Coriandrum sativum), and fennel (Foeniculum vulgare).  The best buffer crops have small flowers to provide pollen and nectar for beneficial insects.  (Big flowers won’t work because the good bugs have small mouth parts).

(3)  If money is tight, plant weeds around field borders.  Grain elevator screenings are free or cheap and contain many weed seeds.  Mixed weeds provide good food and habitat for predatory and parasitic insects.  For example, the braconid wasp Macrocentrus ancylivorus is a major predator of Oriental Fruit Moths (Grapholita molesta) and Peach Twig Borers (Anarsia lineatella).  Planting weeds and wildflowers around peach orchards not only provides pollen and nectar but also necessary alternate hosts such as Ragweed Borer (Epiblema strenuana) and Sunflower Moth (Homoeosoma electellum).  Result:  When the bad bugs arrive, the good bugs are already waiting to eat them.

Hedge Rows:     Windbreaks, greenbelts, shelter belts, and hedgerows all mean the same thing:  Long, thin lines of vegetation planted to slow wind speed, raise humidity, trap snow, reduce soil erosion, and increase soil water absorption.  Good windbreaks greatly multiply biological diversity and provide food and habitat for many species of beneficial birds and insects.  For best results, plant hedgerows along field contours or perpendicular (at right angle) to prevailing winds or water flow.  Greenbelts do not have to be wide in order to be effective; hedges 4 to 8 feet broad or strips of tall-growing perennial grass 1 to 3 feet wide are sufficient for most purposes and will save valuable land for cash crops.  Space windbreaks no closer than 50 feet and no farther than 50 yards apart.  Closer spacing reduces farming efficiency while wider spacing will not control wind speed effectively.  Make shelter belts long to prevent wind from sweeping around the ends.  Minimum length is 10 times the tallest mature tree height in the greenbelt.  Ideal hedgerows contain a variety of plants selected for their economic or environmental value.  Try to plant 40 or more different species per acre or linear mile of windbreak.

Ecology Math:     Creating edge effects requires uncommon thinking, a different way of looking at land.  Most farmers are used to broad square fields.  Edge effect agriculture requires linear thinking:  Thin strips and long, narrow rectangular spaces.  For example, consider a 49-acre farm woodlot, 7 x 7 acres square or approximately 1,456 feet per side x 4 sides = 5,824 linear feet of forest edge.  Take the same woodlot and stretch it into a narrow rectangle 1 acre wide and 49 acres long = (208 feet wide x 2 short sides) + (10,192 feet long x 2 long sides) = 416 + 20,384 = 20,800 linear feet of forest edge.  The border of the narrow woodlot (3.93 miles) is more than 3 1/2 times longer than the border (1.1030 miles) of the square woodlot.  More edges = more life.  Wrap the narrow woodlot around the northwest corner of your farm (or divide the trees into long strips planted at right angle to prevailing winds).  More trees = higher humidity = less water stress = higher crop yields.

Mixed Company:     Each crop has its own architecture, its own micro-climate, and its own assortment of insects and critters that live on its leaves, stems, flowers, and roots.  In short, every species creates its own micro-ecology.  Combine numerous species together and each individual plant becomes an edge where many life forms interact for the benefit of all.  Mixed species have more resistance to pests and more resilience to bad weather.

Ecology By Design:     Mixing crop species is not a new idea; farmers sowed rye and wheat together in the Middle Ages.  The mixed grain crop was called maslin and provided farmers with insurance against catastrophic loss.  If disease or bad weather killed the wheat, stronger rye would survive to make a crop.   Back in colonial times, Thomas Jefferson seeded mixed cover crops of buckwheat, vetch, and turnips to restore fertility to “tired fields”.  Today, mixed cover crops are an essential part of modern agronomy.

Strength In Numbers:     Ideal cover crop mixes contain cool and warm weather species, nitrogen fixing legumes, hardy grasses, broad leaf plants, and root crops.  The idea is to mimic nature by creating an artificial jungle, a jumble of varieties adapted to a wide range of pests, diseases, and growing conditions.  Plant mixtures grow with more vigor and yield than individual species grown in monoculture.  This is an edge effect called synergy, a natural phenomenon where the total is more than the sum of each individual part.

Cover Crop Cocktail:     To make your own cover crop mix, combine 2 cool season grasses + 2 cool season legumes + 2 cool season broad leaf plants + 2 warm season grasses + 2 warm season legumes + 2 warm season broad leaf plants + 2 root crops (tillage radish, turnip, or forage beet).  Drill or broadcast at least 20 pounds seed per acre.

Life Underfoot:     Most farmers think in 2 dimensions (length and width).  Rarely considered is the third dimension, depth.  The soil depths abound with life, and this ecology responds explosively to edge effect management.  Roots need oxygen in order to absorb water and nutrients.  (This is why plants wilt in flooded fields).  Most agricultural soils are oxygen deficient.  Gooey clays, plow pans = compacted layers, and tight subsoils starve soil organisms of essential air.  Impermeable soils also restrict moisture; needed water runs off the land instead of soaking into the earth.  Moisture and oxygen stress greatly reduce crop yields.

Vertical Tillage:     The conventional solution to compacted soils is deep tillage = subsoiling.  Unfortunately, this procedure requires expensive plows and enormous amounts of horse power = BIG tractors or bulldozers.  The effects are also temporary and must be repeated every few years.  A better solution is vertical tillage = verti-tillage = slicing thin crevices into the soil with minimum disturbance to surface vegetation.  Each slit is 3/4 inch wide, 12 to 16 inches deep, and 2 feet apart.  Verti-till fields along the contour for the first 4 or 5 years until soils develop their full potential.  Thereafter, till every few years as needed.  Each slit is like a high-capacity artery supplying water and air directly to the subsoil.  Plant roots flourish along crevice edges.  More roots = higher yields.

Vertical Mulching:     In areas with poor soils, torrential rains, steep slopes or frequent droughts, use vertical mulching to bring problem fields into high production.  Vertical mulching = drilling deep holes or digging deep trenches along the contour or perpendicular (at right angle) to water flow across the land.  Fill the holes or trenches with manure, compost, stable bedding, wood chips, tree bark, coarse peat moss, straw, leaf mold, spoiled hay or similar organic matter.  The holes and trenches conduct air and water deep into the soil so plant roots thrive.  100% to 800% yield increases are frequent, especially in arid lands or difficult soils like heavy clays or stony ground.

Soil Engineering:     For best results use mechanical trenchers and rotary post hole diggers to prepare land for vertical mulching.  Excavations should be as deep as practical, 3 to 8 feet is ideal.  Best holes are 8 to 16 inches in diameter; trenches should be 4 to 12 inches wide.  Space holes and trenches as convenient (as close as 40 inches = 3.3 feet, or as wide as 13.3 to 26.6 feet = 4 to 8 rows 40-inches apart.  Even trenches spaced 50 feet = 15 rows 40-inches apart can dramatically improve yields).  Exact spacing is not essential as more holes and trenches can be dug next season or periodically as time and resources permit.  (Vertical mulching is a LONG TERM soil management technology).

For transplanted crops like tomatoes, peppers, cabbage and melons, space trenches or holes accordingly then fill with compost, potting soil or similar media (1 sand : 1 topsoil : 1 peat is a good mix).  Plant roots quickly grow deep into the subsoil and resulting crops are nearly drought-proof.

If organic matter is scarce or expensive, fill holes or trenches with river sand, river pebbles, or river cobblestones.  (This technique works especially well when trenches are placed directly under permanent tractor paths to prevent soil compaction).  Tree prunings, grain straw, spoiled hay, and green chop or silage make adequate substitutes for compost when treating large fields.  (Any medium will work as long as it has many large holes that allow unrestricted entry of air and water.  In extremis, leave holes and trenches empty; they will eventually fill themselves with eroded soil and plant litter).  Each hole or trench is a high-volume conduit channeling air and water deep into the soil.  Every excavation is another edge between different ecologies and life will proliferate along these boundaries.  More air = more roots = more absorption = higher yields.

Tillage Crops:     In the 1500’s farmers without draft animals used deep rooted crops to “plow” their fields.  They did not have much choice because the alternative was digging fields by hand — a lengthy and laborious task which severely limited the amount of land that could grow food.  It was much easier to sow stock beet = mangle-wurzel (Beta vulgaris) or forage radish (Raphaus sativus variety longipinnatus) and let the plants break up the earth.  Modern farmers call these specialized plants tillage crops or bio-drills because of their ability to penetrate subsoils to depths of 6 feet = 2 meters or more.

The advantage of tillage crops is that they leave tens of thousands of holes (vertical edges) across a field and each hole is a pipeline carrying water and air direct to waiting roots.  Soil life proliferates around these breathing tubes resulting in better plant growth.  For example, average yields increase 15% when upland rice follows a forage radish tillage crop.  As an added benefit, soil erosion is nearly zero because rainwater soaks into the sponge-like earth rather than running off the land.

Agroforestry:     Sunlight is very intense — it contains much more energy than any one crop can absorb.  Thus, it is possible to stack multiple crops on top of each other so that more energy is collected and higher yields obtained.  For example:  Pole Apples grow mostly straight up with very little horizontal spread.  Rows of pole apples planted in a hay field yield 2 crops (fruit and forage) with very little competition between plants.  Edge effects increase dramatically because vertical space is used more efficiently; taller growing fruit trees and ground hugging forage plants are different micro-ecologies.  There are many possible combinations of tree crops and field crops:  Mulberry trees in pasture and English walnut trees in wheat fields are just two examples.  Walk about your farm and look for ways to use vertical spaces = create more edges to increase biodiversity and farm profits.

Water Is Life:     Most crops are water stressed at some point in their growth, usually at critical times like germination, flowering, or fruit development.  The solution to inadequate soil moisture is water management, either active (irrigation) or passive (water conservation).  To ensure ample water supply, every farm should have a watershed management plan; the goal is to trap every drop of water that falls on the land.

The best way to develop a watershed management plan is to don your poncho and walk about the farm while it is raining.  The harder it rains the more you will learn.  Watch where the water comes from and where it goes.  Any place water flows across the land is an EDGE that requires management.

For example, water running down a gully to a stream is wasted moisture = reduced plant growth = lost profits.  Solution:  Top seed low growing clovers to halt water before it runs off your corn field; then build weirs to stop any water that reaches the gully.  (Each row of corn in clover is an edge between different species; every gully and weir is an edge defining separate micro-environments).  Plant useful trees and shrubs behind each weir to take advantage of trapped rainfall.  Stand at the bottom of the gully and watch the results.  If any water escapes then more aggressive management = more edges are needed.

Remember:  The goal of every watershed management plan is zero runoff.  More edges = more trapped water = more life.

Hungry Mouths:     Agriculture is a dirty business that generates substantial pollution.  Smart farmers use edge effects to clean up the mess.  The principle is simple:  For every pollutant there are a host of organisms waiting to eat it.  The trick is to bring food and hungry mouths together; this is best accomplished by creating ecological edges where life thrives.  More edges = more life = more pollutants eaten.

For example, stockyard effluent needs cleaning:  Run dirty water through a sedimentation pond (8 feet deep), aeration lagoon (3 feet deep), filtration marsh (6 inches deep), then into a fish pond or irrigation reservoir.  Result:  Potable water without a costly waste water treatment plant.  4 separate environments each with many edges and different ecologies filled with hungry life forms.  What does not get eaten is absorbed.  Plants, fish and plankton flourish.  Germs and parasites die.

Problem:  The stream running through your property is polluted by an upstream hog farm.  Solution:  Build artificial rapids.  Erect a series of weirs the entire length of the stream.  Each weir is an edge supporting a unique ecology of organisms that thrive in high-oxygen water.  Excess nutrients and harmful microbes are consumed.  1 mile of rapids has the cleansing power of a modern sewage treatment plant.

Mother Nature is quite capable of clearing up the worst pollution; all she needs are places to work.  Provide edges and biology will supply the magic.  More edges = more cleaning power.

Heat On Demand:     Problem:  The fruit industry is 300 miles south of your farm, but you want to grow grapes and peaches.  Solution:  Use edge effects to create favorable micro-climates for trees and vines.  Walk about your farm and wherever there is sufficient catchment area build a pond.  Each pond does not have to be large, but the cumulative effects will be significant.  Water holds lots of heat and each pond acts like a radiator to warm its local environment.  Plant fruit crops on the southeast side of ponds and lakes where temperatures are most favorable.  Every pond is an edge, a boundary between separate ecologies each with its own micro-climate.  Mulch trees and vines with heat-retaining rocks = more edges.  Combining water and rocks can raise canopy temperatures by 5 degrees or more.  A few degrees are all that is needed to protect blossoms from frost.

Linear Agriculture:     Edge effect farming is all about surfaces = boundaries between different ecologies.  Creating more edges fosters more life which in turn enables the environment to support more life.  As life abounds the local ecology grows stronger and more stable.  Crops become more resistant to insects and more resilient to adverse weather.  Result:  Farmers make more money.

Would You Like To Know More?     Please contact the Author directly if you have any questions or need additional information about edge effect agriculture.

Eric Koperek = worldagriculturesolutions@gmail.com

About The Author:     Mr. Koperek is a plant breeder who farms in Pennsylvania during the summer and Florida during the winter.  (Growing two generations each year greatly speeds development of new crop varieties).