"The Historical Roots of Living Mulch and Related Practices"

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bushels/acre). By A.D. 395, farmers in Campania in southern Italy had abandoned 330,000 acres of land (Simkhovitch, 1937). While the quotation that intro- duces this paper oversimplifies the story, the soil conservation record of past civilizations has not been good. How has western civilization managed its soils? Did our European ancestors Reviews learn anything from the mistakes of earlier cultures? And how do our cur- rent soil husbandry practices compare to those of past cultures? Fallow and early European farming The Historical Roots of Living The farmer has always had to deal with soil depletion. The first and most long-standing method of restoring soil Mulch and Related productivity has been the simple fal- lowing of the land (Fussell, 1965). Practices While the use of manures and green manures was known in very early times, fallowing has, until very recently, been Laura K. Paine1 and Helen Harrison2 the most common practice in dealing with declining soil productivity. Early European farmers followed the path of “Civilized man has marched across the Romans, growing mostly soil-de- Additional index words. soil fertility, the face of the earth and left a cover crop, intercrop, crop rotation, pleting grain crops and depending on desert in his footprints” (Carter and conservation tillage. fallow to ameliorate the effects (Fussell, Dale, 1974). 1972). Europe was “saved” from agri- Summary. Since the domestication of cultural decline by another, more-dev- the first crop species, farmers have Few people consider the impor- astating disaster—the bubonic plague, dealt with the problem of soil tance of agriculture or soil conserva- which rose to epidemic proportions in depletion and declining crop yields. tion in the development of cultures. Europe in the middle of the 14th Fallowing of land was the first The rise ofcivilizations depends on the century. The precipitous decline in approach to restoring soil fertility, ability of a culture to produce not just population initiated long-term and and is still the most commonly used enough food for survival, but a surplus method among indigenous farmers. ultimately beneficial changes in Euro- of food. It is only with the production pean agriculture. Alternatives to fallow, such as crop of surpluses and cash crops that popu- rotation and green manures, devel- It is estimated that Europe lost oped in a number of areas. The lation growth, trade, and the trappings between one-eighth and one-third of earliest record of their use is in of civilization can develop. Maintain- its population to the plague between Chinese writings from ca. 500 B.C. ing the productivity of the soil that 1347 and 1351 (Goetz, 1990). This Discussion of these practices is found feeds a population is essential to this population decrease greatly lessened in European agricultural publications process. Inevitably, as population in- the pressure to produce grain for sub- dating from the 16th century. While creases, the pressure on the land to sistence, and created a serious labor these ancient techniques have proven feed it increases. Historical records deficit as well. The large, communal value for soil conservation, their use show that lands that sustained early in modern agriculture is quite limited. fields of the open field system were civilizations, such as Mesopotamia, divided among individual farmers. Renewed interest within the agricul- Greece, Egypt, and Rome, were de- ture community in recent decades has There was a shift toward less labor- resulted in a greater research effort in pleted by intensive farming pressure intensive methods: pasturage and live- the areas of green manures, cover and poor soil husbandry (Carter and stock production, and a concomitant crops, and living-mulch cropping Dale, 1974). This factor contributed increase in the application of manure systems. significantly to the decline of these to the land (Fussell, 1972). A result of cultures. During the last decades of these changes was the development of the Roman Empire, for example, yields crop rotation theory. This practice and of wheat and barley averaged 4 to 6 other conservation methods have bushels per acre. Columella advised served to sustain the productivity of farmers to switch to grapes, “for none Europe’s soils. in Italy can remember when grain in- creased four-fold” (this would result Crop rotation in a “good” yield for that time, of 7 The development of crop rota- HortTechnology · Apr./June 1993 3(2) 137 tion theory rested on an understand- low seasons, and many involved green “Tillage is breaking and dividing ing that different crops vary in the manure crops for the first time. the Ground by Spade, Plough, Hoe or amount of nutrients they take from the other Instruments, which divide by a soil, and that some (notably legumes) Tillage fort of Attrition (or Contusion) as serve to enhance the soil’s ability to “The finer Land is made by Till- Dung does by Fermentation” (Tull, sustain subsequent crops. There was age, the richer will it become, and the 1731). no accompanying understanding of more Plants it will maintain” (Tull, Furthermore, he was quick to plant nutrition, a science that was not 1731). point out the other advantage of his to mature until the middle of the 19th system—tillage not only killed sprout- century With these words, Jethro Tull ing weeds in the field, but, by reducing Thomas Tusser’s Five Hundred started what became a revolution in the amount of manure used, one could Points of Good Husbandry, published the practice of agriculture. Born in cut down the amount of weed seed in 1580, was one of the earliest widely 1674, Tull was an organist and gentle- introduced into the field in the first distributed volumes on agriculture. man farmer (Fussell, 1973). He ap- place. Thus, tillage served to: The following excerpt (with interpre- proached farming scientifically, con- “. force open her (the land’s) tation in parentheses) reflects 16th ducting comparative experiments on Magazines with the Hoe, which will century understanding of soil conser- his Oxfordshire, England, estate. Here, thence procure (for) them at all times vation and crop rotation: Tull explored the role of tillage in Provision in abundance, and also free making land more productive. Noth- them from Intruders; I mean, their Otes, rie or else barlie, and wheat ing in the agricultural system of the spurious Kindred, the Weeds, that that is gray 18th century was conducive to the use robbed them of their too scanty Al- brings land out of comfort, and soon of tillage. Farm implements were simple lowance” (Tull, 1731). to decay. and crude. A farmer’s entire array of While Tull’s theories did not have One after another, no comfort machinery often consisted of a plow an immediate impact on farming in betweene, and a harrow (Fussell, 1965). The Europe, their long-term effect on ag- is crop upon crop, as will quickly be draft animals used to power these riculture has been great. In the de- seen implements did not have the benefit of cades since Tull introduced the con- (Oats, rye, barley and wheat deplete the breeding for size and strength. Only cept of tillage, it has become an inte- soil) the top few inches of soil were ever gral part of western agriculture. Today disturbed. Seed was broadcast by hand tillage, with its attendant drawbacks, Still crop upon crop many fermers do in the spring and maintenance of the can be an obstacle to sustainability. take. field during the cropping season was Goals of green manure and cover crop and reape little profit for greediness minimal. advocates in recent years have been the sake. Thus, Tull was forced to invent amelioration of the negative effects of Though breadcorne and drinkcorn the equipment he needed—the seed tillage. such croppers do stand: drill and the cultivator, which he is said Count peason or brank, as a comfort to have constructed from pipe organ Soil fertility theory after to land. parts. The seed drill allowed for the Tull (Some greedy farmers sow crop af- planting of seed in distinct rows, so There were many other research- ter crop of wheat or barley, but receive that cultivation between rows during ers working in the 18th century to diminishing returns. Peas or buckwheat the growing season was made possible. unlock the secrets of the soil and plant help to restore soil fertility.) The benefits derived from this ap- nutrition. Several important concepts proach included reduction of seed were derived from this work, such as Some useth at first a good fallow to waste and reduction in weed pressure the knowledge that humus resulted make. on the crop. Using this system, Tull’s from the decomposition of plants and To sowe thereon barlie, the better to yields far outstripped those of his neigh- provided water-holding capacity as well take. bors, even without the regular addi- as sustenance for crops. Humus im- Next that to sowe pease, and of that to tion of manure. He recorded his ob- parts a dark color to soil, and the sowe wheat, servations of this phenomenon in a degree of darkness was held to reflect Then fallow againe, or lie lay for thy book entitled Horse Hoeing Hus- the richness of the soil. The culmina- neat. bandrie: An Essay on the Principles of tion of this research was the “Humus (In this verse, Tusser sets out a Vegetation and Tillage (Tull, 1731). Theory,” which was developed in the rotation that calls for fallow, barley, Like Tusser, Tull worked without the last decades of the 18th century (Fus- peas, wheat, then fallow again or pas- benefit of an understanding of plant sell, 1971). The Humus Theory went ture. The term “neat” refers to cattle.) nutrition.
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