Abstract:     This experiment measures the productivity of a 3-species polyculture of flint corn, pole beans, and winter squash.  Heritage varieties are grown in traditional hills with fish fertilizer.  Areas between hills are untended and covered with native weeds. 

Experimental Location:     Butler County, Pennsylvania, United States of America.  40.8606 degrees North Latitude, 79.8947 degrees West Longitude.

Climate:     Butler County has a temperate climate with cold winters.  Average annual temperature = 48.75 degrees Fahrenheit = 9.3 degrees Centigrade.  Average yearly rainfall = 41.85 inches = 106.299 centimeters.  Average yearly snowfall = 37 inches = 93.98 centimeters.  Average Last Spring Frost (36 degrees Fahrenheit) = 26 May.  Average First Fall Frost (36 degrees Fahrenheit) = 23 September.  Frost Free Growing Season = 119 days (about 4 months).

Experimental Plot Size:     1/4 acre = 10,890 square feet exactly = 104 x 104 feet approximately = 10,816 square feet nominal measure.

Experimental Design:     A 1/4-acre plot was planted each year.  Crops were not rotated; hills were replanted each year in keeping with traditional Indian practice.  The experiment was repeated for 10 years (to account for weather variability between years).  10 data sets ensure reliable averages for accurate conclusions.

Soil Type:     Heavy Clay Loam

Crop Rotation:     Field was fallowed in native weeds for 7 years prior to experiment.  Hilled crops were NOT rotated.  Hills were replanted each year following traditional Indian methods.  (Historical sources record that native farmers practiced long rotations.  When soils became exhausted, hills were moved or fields abandoned).

Tillage:     There is no easy way to make Indian planting hills using conventional farm machinery.  Consequently, tree planting augers were used to dig holes 2 feet wide x 2 1/2 feet deep.  Holes were then refilled with excavated soil to make traditional mounds approximately 1 foot high.  Augers save considerable hand labor while preserving weed ground cover.  (The idea is to use native weeds as a multi-species cover crop.  Cash crops are planted in hills surrounded by weeds.  The weeds protect crops from insect pests).

Plant Density:     Hills were equidistantly spaced every 4 feet on center = 26 rows x 26 hills within each row = 676 mounds in the 1/4 acre research plot.  Each hill contained 4 maize plants seeded evenly around a circle 1-foot diameter.  When maize plants reached 2 feet high (4 to 8 leaves), 1 pole bean seed was planted 3 inches from each maize stalk.  676 hills x 4 maize plants per hill = 2,704 maize plants per 1/4 acre.  676 hills x 4 bean plants per hill = 2,704 bean plants per 1/4 acre.  Squash plants were set every other row and every other mound within alternate rows  = 8 feet x 8 feet apart = 13 rows x 13 mounds within each row = 169 squash plants per 1/4 acre.

Plants Per Acre:     10,816 maize plants; 10,816 bean plants; and 676 winter squash plants per acre.  For ease of comparison, yields are summarized in pounds per acre.

Transplant Size:     Squash transplants were 4 weeks old.  All plants were about 4 inches high.  Transplants were grown in 3 1/2 inch interior diameter peat pots filled with crumbled, dried cow manure.

Crop Varieties:     Floriani Red Flint Corn; Scarlet Runner Pole Bean; and Waltham Butternut Winter Squash.

Predominant Weed Species:     Pigweed (Amaranthus blitum), Lambs Quarters (Chenopodium album), Bull Thistle (Cirsium vulgare), Foxtail Millet (Setaria species), and Morning Glory (Ipomoeae species).

Weed Management:     No attempt was made to eradicate weeds.  Fields were mowed as close to ground level as practical immediately prior to seeding and transplanting.  Cut weeds were used as mulch for planting mounds, about 2 1/4 pounds (dry weight) of weed mulch per hill.  Squash vines overwhelmed most weeds.  Wild morning glory vines were the most difficult to control and some hills (about 15 percent on average) were nearly overrun.  Hand pruning was necessary to prevent crop loss.  A second mowing (when squash vines started to run) effectively suppressed weed growth, but squash and weeds battled for dominance in the “No Man’s Land” between hills.

Irrigation:     Crops were NOT irrigated, in keeping with traditional practice.  There is no historical record of Eastern North American Indians irrigating their crops, probably because there was little need to do so and also because native farmers did not have effective irrigation technology.  Carrying water in gourds, bark buckets, and clay pots is grueling labor.

Insect Control:     No active measures were taken to control insect pests.  Native weeds provided food and shelter for many beneficial insects that protected crops.

Fertilizer:     Fresh trash fish or fish scraps were too difficult to obtain in quantity, so fish meal (10 percent nitrogen, 5 percent phosphorous, 0 percent potassium) was used instead.  Each maize and squash plant received 1/3 cup (1.66 scale ounces) of fish meal mixed with the soil at planting.  This is the approximate equivalent of 119 pounds of available nitrogen and 59 pounds of phosphorous per acre.  Potassium was provided in the form of wood ashes, 6 scale ounces top dressed over each hill when squash vines were transplanted = about 1/2 ton (1,000 pounds) per acre = 70 pounds of available potash per acre.  (Fertilizing crops was NOT a common practice among North American Indians.  Native farmers learned these techniques from Europeans.  For example:  In colonial times, French farmers in Normandy fertilized their fields with herring).

10-Year Maize Yield Summary:     2,997.7 pounds per acre = 1.49885 tons per acre = 53.5 bushels per acre.  Range = 1,853 to 3,960 pounds per acre = 33.08 to 70.71 bushels per acre.  Average Yield per Plant = 4.43 ounces.  1 bushel of clean, shelled corn = 56 pounds.

10-Year Bean Yield Summary:     520.8 pounds per acre = 0.2604 ton per acre = 8.68 bushels per acre.  Range = 336 to 688 pounds per acre = 5.6 to 11.46 bushels per acre.  Average Yield per Plant = 0.048 pound = 0.768 ounce.  1 bushel of clean, dried beans = 60 pounds.

10-Year Winter Squash Yield Summary:     7,293.6 pounds per acre = 3.6468 tons per acre.  Range = 5,412 to 8,776 pounds per acre = 2.706 to 4.388 tons per acre.  Average Fruits per Acre = 3,000.  Average Fruit Weight = 2.43 pounds = 2 pounds 6.88 ounces.  Average Yield per Plant = 10.78 pounds = 10 pounds 12.48 ounces.  Average Fruits per Plant = 4 (4.43 exactly).  Note:  Because of their size, winter squash and pumpkins are not measured in bushels.

Estimated Carrying Capacity:     A 1-acre polyculture of maize, beans, and squash with hills spaced 4 feet apart feeds 1 family (4 people) for 1 year = 2.05 pounds of corn meal per person per day + 0.3567 pound (5.7 ounces) of dried beans for each person daily + 4.99 pounds of fresh winter squash per person daily.  This is more than sufficient to support a small family, especially if rations are supplemented by hunting and gathering.

Experimental Data (Maize):     Yields are recorded in pounds of clean, air dried corn per 1/4 acre.  All numbers are rounded down to the nearest whole pound.  Hills are spaced 4 x 4 feet equidistantly.  26 rows x 26 hills within each row = 676 hills x 4 corn plants per hill = 2,704 corn plants per 1/4 acre.

Year                    Maize Yield in Pounds per 1/4 Acre

2007                    463

2008                    895

2009                    590

2010                    848

2011                    556

2012                    990

2013                    934

2014                    804

2015                    689

2016                    727

10-Year Total Yield          7,496 pounds

Average Yield                   749.6 pounds per 1/4 acre

Yield Range                      463 to 990 pounds per 1/4 acre

Average Yield per Plant = 0.2772 pound = 4.43 ounces

Experimental Data (Pole Beans):     Yields are recorded in pounds of clean, air dried beans per 1/4 acre.  All numbers are rounded down to the nearest whole pound.  Hills are spaced 4 x 4 feet, equidistantly.  26 rows x 26 hills within each row = 676 hills x 4 bean plants per hill = 2,704 bean plants per 1/4 acre.

Year                    Bean Yield in Pounds per 1/4 Acre

2007                    103

2008                    146

2009                    92

2010                    132

2011                    84

2012                    161

2013                    124

2014                    172

2015                    128

2016                    160

10-Year Total Yield          1,302 pounds

Average Yield                   130.2 pounds per 1/4 acre

Yield Range                       84 to 172 pounds per 1/4 acre

Average Yield per Plant = 0.048 pound = 0.768 ounce.

Experimental Data (Winter Squash):     Yields are recorded in pounds of fresh fruit per 1/4 acre.  All numbers are rounded down to the nearest whole pound.  Squash plants are spaced every other row and every other hill within alternate rows = 13 rows x 13 hills within each row = 8 x 8 feet apart = 169 plants per 1/4 acre.

Year                    Squash Yield in Pounds per 1/4 Acre

2007                    1,353

2008                    2,138

2009                    2,025

2010                    1,497

2011                    1,446

2012                    2,140

2013                    2,040

2014                    1,669

2015                    2,194

2016                    1,732

10-Year Total Yield          18,234 pounds

Average Yield                   1,823.4 pounds per 1/4 acre

Yield Range                      1,353 to 2,194 pounds per 1/4 acre

Average Fruits per 1/4 Acre = 750

Average Fruit Weight = 2.43 pounds = 2 pounds 6.88 ounces

Average Yield per Plant = 10.78 pounds = 10 pounds 12.48 ounces

Average Fruits per Plant = 4 (4.43 exactly)

Commentary:     Traditional polycultures of corn, beans and squash are not commercially practical because planting and harvest cannot be mechanized.  Fish meal fertilizer is also un-economic because it costs more ($0.72 per pound) than most chemical or organic plant foods.  Planting nitrogen-fixing cover crops and sowing seeds in rows is far less expensive than traditional hill cultivation.

Strip cropping combines the ecological advantages of polycultures with the economic efficiency of farm machinery.  Plant narrow strips of cash crops following land contours.  (Adjust strip width to fit farm equipment).  Seed or transplant unrelated crops on adjacent strips to take advantage of edge effects.  Planting multiple species on each field increases biodiversity and greatly reduces crop pests.

Related Publications:     No-Till Hungarian Stock Squash; 2012 Tomato and Sweet Potato Polyculture Trial; and The Edge Effect.

Other Articles of Interest:     Crop Rotation Primer; Biblical Agronomy; The Twelve Apostles; “Can Sunnhemp Outgrow Morning Glory?”; Worm Farming; Managing Weeds as Cover Crops; Weed Seed Meal Fertilizer; Trash Farming; Earthworm Primer; Planting Maize with Living Mulches; Living Mulches for Weed Control; Upside Down Potatoes; and Crops Among the Weeds.

Would You Like To Know More?     Please contact the Author directly if you have any questions or need additional information about modern or traditional polycultures.  Please visit:     http://www.worldagriculturesolutions.com  — or —  send an e-mail to:  http://www.worldagriculturesolutions@gmail.com  — or —  send a letter to:  Eric Koperek, Editor, World Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 United States of America.

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).