The Enclosures in England: An Economic Reconstruction

by Harriett Bradley Fitt

When, however, the virgin soil is broken up by the plough and brought into cultivation the native vegetation and the crop are alike removed, and therefore the sources of gain are considerably reduced. The losses, on the other hand, are much intensified. Rain water more readily penetrates, carrying dissolved substances with it: biochemical decompositions also proceed. In consequence the soil becomes poorer, and finally it is reduced to the same level as the rate of gain of nitrogenous matter. A new and lower equilibrium level is now reached about which the composition of the soil remains fairly constant; this is determined by the same factors as the first, i. e. the composition of the soil, climate, etc.

Thus each soil may vary in composition and therefore in fertility between two limits: a higher limit if it is kept permanently covered with vegetation such as grass, and a lower limit if it is kept permanently under the plough. These limits are set by the nature of the soil and the climate, but the cultivator can attain any level he likes between them simply by changing his mode of husbandry. The lower equilibrium level is spoken of as the inherent fertility of the soil because it represents the part of the fertility due to the soil and its surroundings, whilst the level actually reached in any particular case is called its condition or "heart", the land being in "good heart "or "bad heart", according as the cultivator has pushed the actual level up or not; this part of the fertility is due to the cultivator's efforts.

The difference between the higher and lower fertility level is not wholly a question of percentage of nitrogen, carbon, etc. At its highest level the soil possesses a good physical texture owing to the flocculation of the clay and the arrangement of the particles: it can readily be got into the fine tilth needed for a seed bed. But when it has run down the texture becomes very unsatisfactory. Much calcium carbonate is also lost during the process: and when this constituent falls too low, the soil becomes "sour" and unsuited for crops.

The simplest system of husbandry is that of continuous wheat cultivation, practiced under modern conditions in new countries. When the virgin land is first broken up its fertility is high; so long as it remains under cultivation this level can no longer be maintained, but rapidly runs down. During this degradation process considerable quantities of plant food become available and a succession of crops can be raised without any substitution of manure ... After a time the unstable period is over and the new equilibrium level is reached at which the soil will stop if the old husbandry continues. In this final state the soil is often not fertile enough to allow of the profitable raising of crops; it is now starving for want of those very nutrients that were so prodigally dissipated in the first days of its cultivation, and the cultivator starves with it or moves on.

Fortunately recovery is by no means impossible, though it may be prolonged. It is only necessary to leave the land covered with vegetation for a period of years when it will once again regain much of the nitrogenous organic matter it has lost.[[39]]

Dr. Russell adds that soil-exhaustion is essentially a modern phenomenon, however, and gives the following reasons for supposing that the medieval system conserved the fertility of the soil. First, the cattle grazed over a wide area and the arable land all received some dung. Thus elements of fertility were transferred from the pasture land to the smaller area of tilled land. This process, he admits, involved the impoverishment of the pasture land, but only very slowly, and the fertility of the arable was in the meanwhile maintained. Secondly, the processes of liming and marling the soil were known, and by these means the necessary calcium carbonate was supplied. Thirdly, although there was insufficient replacement of the phosphates taken from the soil, the yield of wheat was so low that the amount of phosphoric acid removed was small, and the system was permanent for all practical purposes. One of the facts given in substantiation of this view is that the yield after enclosure increased considerably.[[40]]

In discussing these points, it will be well to begin with the evidence as to exhaustion afforded by the increased yield under enclosure. The improvement in yield took place because of the long period of fallow obtained when the land was used as pasture; or, in the eighteenth century, with the increase in nitrogenous organic matter made possible when hay and turnips were introduced as field forage crops. That is, the increase in yield depended either upon that prolonged period of recuperation which will restore fertility, or upon an actual increase in the amount of manure used. Apparently, then, open-field land had become exhausted, since an increase in yield could be obtained by giving it a rest, without improving the methods of cultivation, etc., or by adding more manure.

There was not, as Dr. Russell supposes, enough manure under the medieval system of husbandry to maintain the fertility of the soil. It is true that the husbandman understood the value of manure, and took care that the land should receive as much as possible, and that he knew also of the value of lime and marl. But, as Dr. Simkhovitch says:

It is not within our province to go into agrotechnical details and describe what the medieval farmer knew, but seldom practiced for lack of time and poor means of communication, in the way of liming sour clay ground, etc. Plant production is determined by the one of the necessary elements that is available in the least quantity. It is a matter of record that the medieval farmer had not enough and could not have quite enough manure, to maintain the productivity of the soil.[[41]]

The knowledge of the means of maintaining and increasing the productivity of the soil is one thing, but the ability to use this knowledge is another. The very origin and persistence of the cumbersome common-field system in so many parts of the world is sufficient testimony as to the impossibility of improving the quality of the soil in the Middle Ages. The only way in which these men could divide the land into portions of equal value was to divide it first into plots of different qualities and then to give a share in each of these plots to each member of the community. They never dreamed of being able to bring the poor plots up to a high level of productivity by the use of plentiful manuring, etc., but had to accept the differences in quality as they found them. The inconvenience and confusion of the common-field system were endured because, under the circumstances, it was the only possible system.