Practical Applications of the Indore Process (contd.)
Before taking up research on cotton at the newly founded Institute of Plant Industry at Indore in 1924, a survey of cotton growing in the various parts of India was undertaken. At the same time the research work in progress on this crop was critically examined.
The two most important cotton-growing areas in India are: (1) the black cotton soils of the Peninsula, which are derived from the basalt; (2) the alluvium of North-West India, the deposits left by the rivers of the Indo-Gangetic plain.
In the former there are thousands of examples which indicate beyond all doubt the direction research on this crop should take. All round the villages on the black cotton soils, zones of highly manured land rich in organic matter occur. Here cotton does well no matter the season: the plants are well grown and free from pests: the yield of seed cotton is high. On the similar but unmanured land alongside the growth is comparatively poor: only in years of well distributed rainfall is the yield satisfactory. The limiting factor in growth is the development, soon after the rains set in, of a colloidal condition which interferes with aeration and impedes percolation. This occurs on all black soils, but organic matter mitigates the condition.
On the alluvium of North-West India, a similar limiting factor occurs. Here cotton is grown on irrigation, which first causes the fine soil particles to pack and later on to form colloids. In due course the American varieties in particular show by their growth that they are not quite at home. The anthers often fail to function properly, the plants are unable to set a full crop of seed, the ripening period is unduly prolonged, and the fibre lacks strength, quality, and life. The cause of this trouble is again poor soil aeration, which appears in these soils to lead to a very mild alkali condition. This, in turn, prevents the cotton crop from absorbing sufficient water from the soil. One of the easiest methods of preventing this packing is by assisting the soil to form compound particles with the help of dressings of humus.
The basis of research work on cotton in India was therefore disclosed by a study in the field of the crop itself. The problem was how best to maintain soil aeration and percolation. This could be solved if more humus could be obtained. Good farming methods therefore provided the key to the cotton problems of India.
A study of the research work which has been done all over the world did nothing to modify this opinion. The fundamental weakness in cotton investigations appeared to be the fragmentation of the factors, a loss of direction, failure to define the problems to be investigated, and a scientific approach on far too narrow a front without that balance and stability provided by adequate farming experience.
Steps were therefore taken to accelerate the work on the manufacture of humus which had been begun at the Pusa Research Institute. The Indore Process was the result. It was first necessary to try it out on the cotton crop. The results are summed up in the following Table:
The increase general fertility at Indore
Area in acres of improved land under cotton
Average yield in lb. per acre
Yield of the best plot of the year in lb. per acre
Rainfall in inches
27.79 (distribution good)
40.98 (a year of excessive rainfall)
23.11 (distribution poor)
The figures show that, no matter what the amount and distribution of rainfall were, the application of humus soon trebled the average yield of seed cotton -- 200 lb. per acre -- obtained by the cultivators on similar land in the neighbourhood.
In preparing humus at Indore one of the chief wastes was the old stalks of cotton. Before these could be composted they had to be broken up. This was accomplished by laying them on the estate roads, where they were soon reduced by the traffic to a suitable condition for use as bedding for the work-cattle prior to fermentation in the compost pits.
The first cotton grower to apply the Indore Process was Colonel (now Sir Edward) Hearle Cole, C.B., C.M.G., at the Coleyana Estate in the Montgomery District of the Punjab, where a compost factory on the lines of the one at the Institute of Plant Industry at Indore was established in dune 1932. At this centre all available wastes have been regularly composted since the beginning: the output is now many thousands of tons of finished humus a year. The cotton crop has distinctly benefited by the regular dressings of humus; the quality of the fibre has improved; higher prices are being obtained; the irrigation water required is now one-third less than it used to be. The neighbouring estates have all adopted composting: many interested visitors have seen the work in progress. One advantage to the Punjab of this work has, however, escaped attention, namely, the importance of the large quantities of well-grown seed, raised on fertile soil, contributed by this estate to the seed distribution schemes of the Provincial Agricultural Department. Plant breeding to be successful involves two things -- an improved variety plus seed for distribution grown on soil rich in humus.
The first member of an Agricultural Department to adopt the Indore Method of composting for cotton was Mr. W. J. Jenkins, C.I.E., when Chief Agricultural Officer in Sind, who proved that humus is of the greatest value in keeping the alkali condition in check, in maintaining the health of the cotton plant, and in increasing the yield of fibre. At Sakrand, for example, no less than 1,250 cartloads of finished humus were prepared in 1934-5 from waste material such as cotton stalks and crop residues.
During recent years the Indore Process has been tried out on some of the cotton farms in Africa belonging to the Empire Cotton Growing Corporation. In Rhodesia, for example, interesting results have been obtained by Mr. J. E. Peat at Gatooma. These were published in the Rhodesia Herald of August 17th, 1939. Compost markedly improved the fibre and increased the yield not only of cotton but also of the rotational crop of maize.
Why cotton reacts so markedly to humus has only just been discovered. The story is an interesting one, which must be placed on record. In July 1938 I published a paper in the Empire Cotton Growing Review (vol. xv, no. 3, 1938, p. 186) in which the role of the mycorrhizal relationship in the transmission of disease resistance from a fertile soil to the plant was discussed. In the last paragraph of this paper the suggestion was made that mycorrhiza 'is almost certain to prove of importance to cotton and the great differences observed in Cambodia cotton in India, in yield as well as in the length of the fibre, when grown on (1) garden land (rich in humus) and (2) ordinary unmanured land, might well be explained by this factor'. In the following number of this Journal (vol. xv, no. 4, 1938, p. 310) I put forward evidence which proved that cotton is a mycorrhiza-former. The significance of this factor to the cotton industry was emphasized in the following words:
'As regards cotton production, experience in other crops, whose roots show the mycorrhizal relationship, points very clearly to what will be necessary. More attention will have to be paid to the well tried methods of good farming and to the restoration of soil fertility by means of humus prepared from vegetable and animal wastes. An equilibrium between the soil, the plant and the animal can then be established and maintained. On any particular area under cotton, a fairly definite ratio between the number of live stock and the acreage of cotton will be essential. Once this is secured there will be a marked improvement in the yield, in the quality of the fibre and in the general health of the crop All this is necessary if the mycorrhizal relationship is to act and if Nature's channels of sustenance between the soil and the plant are to function. Any attempt to side-track this mechanism is certain to fail.
'The research work on cotton of to-morrow will have to start from a new base line -- soil fertility. In the transition between the research of to-day and that of the future, a number of problems now under investigation will either disappear altogether or take on an entirely new complexion. A fertile soil will enable the plant to carry out the synthesis of proteins and carbohydrates in the green leaf to perfection. In consequence the toll now taken by fungous, insect and other diseases will at first shrink in volume and then be reduced to its normal insignificance. We shall also hear less about soil erosion in places like Nyasaland where cotton is grown, because a fertile soil will be able to drink in the rainfall and so prevent this trouble at the source.'
Confirmation of these pioneering results soon followed. In the Transactions of the British Mycological Society (vol. xxii, 1939, p. 274) Butler mentions the occurrence of mycorrhiza as luxuriantly developed in cotton from the Sudan and also in cotton from the black soils of Gujerat (India). In the issue of Nature of July 1st, 1939, Younis Sabet recorded the mycorrhizal relationship in Egypt. In the Empire Cotton Growing Review of July 1939 Dr. Rayner confirmed the existence of mycorrhiza in both Cambodia and Malvi cotton grown at my suggestion by Mr. Y. D. Wad at Indore, Central India, in both black cotton soil and in sandy soil from Rajputana.
As is well known, the leaves of the sisal plant yield about 93 per cent. of waste material and about 7 per cent. of fibre, of which not more than 5 per cent. is ordinarily extracted. The wastes are removed from the decorticators by a stream of water, usually to some neighbouring ravine or hollow in which they accumulate. Sometimes they are led into streams or rivers. The results are deplorable. Putrefaction takes place in the dumps and nuisance results, which can be detected for miles. The streams are contaminated and the fish are killed. On account of these primitive methods of waste disposal, the average sisal factory is a most depressing and disagreeable spot. Further, the water used in these operations -- which has to be obtained at great expense by sinking wells or boreholes, by making dams or reservoirs, and then raised by pumping plants -- is allowed to run to waste. Two of the pressing problems, therefore, of the sisal industry are: (1) the conversion of the solid residues, including the short fibres, into some useful product like humus, and (2) the use of the waste water for raising irrigated crops.
These two problems have been successfully solved on Major Grogan's estate at Taveta in Kenya, by the Manager, Major S. C. Layzell, M.C. The work began in 1935 and has been steadily developed since. An account of the results was published in the East African Agricultural Journal of July 1937.
The first problem was to separate the liquid in the flume waste from the solids. At Taveta all the waste from the decorticator is passed over a grid at the end of the flume. The grid retains the solids and allows the acid 'soup' to pass into a concrete sump below, from which it is carried by a suitably graded channel, with a fall of 1 in 1,000, to the irrigated area. From the grid the solid waste is moved on slatted trucks (the usual four-wheel frame constructed of timber with a platform of slats arranged at right angles to the track) to a concrete basin where they are allowed to drain The drainage water from this basin is led by a small irrigation furrow to another area where it is utilized for growing crops. There are thus two sources of irrigation water -- the main flume water and the drainage from the loaded trucks (Plate I).
PLATE I: Conversion of sisal waste.
Filtering the waste.
Irrigation with waste-water.
The lay out of the composting ground is important. Sisal poles, in groups of four, equally spaced, are arranged on both sides and at right angles to the rail track. On these poles, placed a foot apart for providing aeration from below, the waste is lightly spread to a height of 2 feet in heaps measuring 15 feet by 4 feet. As all new heaps require a starter, any estate making compost for the first time should obtain a small supply of freshly made humus from some other sisal estate which has adopted the Indore Process. A few handfuls of this old compost, distributed evenly in the heaps, is sufficient to start fermentation. The waste is left on the poles for thirty days during which the breaking-down process, by means of thermophylic bacteria, begins. The temperature rises to a point where it is impossible to bear one's hand in the heap.
The first turn takes place thirty days after the first formation of the heap when the contents of two heaps are run together into one, as by this time the volume has considerably decreased. After the first turn the decomposition is carried a stage further, mainly by fungi. During this phase the whole heap is often covered each morning with a long-stemmed toadstool (Plate II).
PLATE II. Conversion of sisal waste.
Light railway and foundation of sisal poles.
Turned heaps with layers of elephant grass.
At the end of another thirty days the second turn takes place. The ripening process then begins and is completed about the ninetieth day after the original heaps were made. Major Layzell writes that the final product resembles first-class leaf mould and contains 1.44 per cent. of nitrogen. On the basis of its chemical composition alone the compost has been valued locally at £2 a ton.
A large portion of the humus is devoted to the sisal nurseries in order that all new areas can be started with vigorous and properly grown plants. The remainder finds its way to the areas producing sisal.
The sisal plant only does well on fertile soil and therefore needs intensive rather than extensive cultivation. Whenever this is forgotten the enterprise ends in bankruptcy for the reason that, as the soil near the factory is exhausted, the lead to the decorticators soon eats up the profit. The game is no longer worth the candle. The conversion of the wastes into humus will therefore solve this problem: the fertility of the land round the factory can be maintained and even improved. Further, the dumps of repulsive sisal waste will be a thing of the past.
The labour employed in dealing with the waste and turning the heaps from a decorticator producing 120 tons of fibre per month is thirty-four with two head men. Sixteen additional men were taken up on the grid and with the trucks, so that a labour force of fifty in all with two head men was needed for making compost at this centre. There is no difficulty in handling sisal wastes provided the workmen are given a supply of some cheap oil for protecting the skin, otherwise the juice of the leaves produces eczema on the arms and legs of those engaged on the work.
The flume liquid is mainly used for growing food crops for the labour force so as to improve the usual set ration of mealie-meal, beans, and salt. The psychological effect of all this on the labourers has been remarkable: the spectacle of a large area of bananas, sugar-cane, citrus plants, and potatoes removes all fear of a possible lack of food from the minds of the workers and their families: they feel safe. Further, their physical health and their efficiency as labourers rapidly improve. A guaranteed food-supply has proved a great attraction to labour and has provided a simple and automatic method of recruitment.
At Taveta the soil contains a good deal of lime so that the prior neutralization of the acid irrigation water is unnecessary. On other estates this point might have to receive attention. Perhaps the easiest way to get rid of the acidity would be to add sufficient powdered crude limestone to the flume water just after the solids have been separated for composting.
Two conditions must be fulfilled before the methods worked out at Taveta can be adopted elsewhere: (1) there must be a suitable area of flat land near the factory for growing irrigated crops; (2) the general layout must be such that there is ample room for a composting ground to which the wastes can be taken by a light railway and from which the finished humus can be easily transported to the irrigated area and to the rest of the estate.
One obvious improvement in the manufacture of humus on a sisal estate must be mentioned. Animal residues must be added to the vegetable wastes. If it is impossible to maintain sufficient live stock for all the sisal waste, two grades of humus should be made: first grade with animal manure for the parent plants and the nurseries, second grade for the plants which yield fibre.
One of the great weaknesses in British agriculture at the moment is the dependence of our live stock -- such as pigs, poultry, and dairy animals -- on imported foodstuffs. Our animal industry is becoming just as unbalanced as regards the supply of nutriment grown on fertile soil as our urban population. One of the animal foods imported in large quantities is maize. Unfortunately a large proportion of this import is being grown on worn-out soils. We are feeding our animals and indirectly ourselves on produce grown anywhere and anyhow so long as it is cheap.
Mother earth, however, has registered an effective protest. The maize soils of such areas as Kenya and Rhodesia soon showed signs of exhaustion. The yields fell off. Any one who has had any practical experience of maize growing could have foretold this. This crop requires a fertile soil.
The maize growers of Kenya, Rhodesia, and South Africa soon learnt this lesson. The constant cropping of virgin land with an exhausting crop rapidly reduced the yield. This happened just as the Indore Process was devised. Its application to the maize fields of Kenya and Rhodesia led to good results. The composting of the maize stalks and other vegetable residues, including green-manure crops, was taken up all over Kenya and Rhodesia.
Two examples out of many of the results which are being obtained may be quoted: at Rongai in Kenya, Mr. J. E. A. Wolryche Whitmore has adopted the Indore Process on three farms. The working oxen are being bedded down during the night with dry maize stalks, wheat-straw, grass, and other roughage available. After a week under the cattle this is composted in pits with wood-ashes and earth from under the animals. If insufficient earth is used a high temperature is not maintained. Two turns at intervals of a month yield a satisfactory product after ninety days. The effect on the maize crop is very marked. In Rhodesia, Captain J. M. Moubray has obtained similar results. These are described in detail in Appendix B).
One of the pests of maize in Rhodesia -- the flowering parasite known locally as the witch-weed (Striga lutea) -- can be controlled by humus. This interesting discovery was made by Timson whose results were published in the Rhodesia Agricultural Journal of October 1938. Humus made from the soiled bedding in a cattle kraal, applied at the rate of 10 tons to the acre to land severely infested with witch-weed, was followed by an excellent crop of maize practically free from this parasite. The control plot alongside was a red carpet of this pest. A second crop of maize was then grown on the same land. Again it was free from witch-weed. This parasite promises to prove a valuable censor for indicating whether or not the maize soils of Rhodesia are fertile. If witch-weed appears, the land needs humus; if it is absent, the soil contains sufficient organic matter. Good farming will therefore provide an automatic method of control.
Humus is bound to affect the quality of maize as well as the yield. In the interests both of the maize-exporting and the maize-importing countries, a new system of grading and marketing the produce of fertile soil should be introduced. Maize grown on land manured with properly made humus and without the help of artificials should be so described and graded. Only in this way can well-grown produce come into its own. It should be clearly distinguished in its journey from the field to the animal and kept separate from inferior maize. Purchasers will then know that such graded produce fed to their live stock will have been properly grown. They will soon discover that it suits their animals. This question of grading produce according to the way it is grown applies to many other crops besides maize. Its importance to the future of farming and the health of the nation is referred to in a later chapter.
By far the most important food crop in the world is rice. It will be interesting therefore to see what response this cereal makes to humus. We should expect it would be considerable, because the rice nurseries are always heavily manured with animal manure and just before transplanting the seedlings are much richer in nitrogen than at any further stage in the life of the plant.
The first trial of the Indore Process was made by the late Mrs. Kerr at the Leper Home and Hospital, Dichpali in H.E.H. the Nizam's Dominions. Her reaction after reading The Waste Products of Agriculture in 1931 was: 'If he is right it will mean the utter economic revolution of India's villages.' Rice was selected as the crop on which to test the method. She died while the trial was in progress. The results are summed up in a letter from her husband, the Rev. G. M. Kerr, dated Dichpali, November 2nd, 1933, as follows:
'We have cut three and entirely average portions of our rice fields. No. 1 plot had 1.25 to 1.5 inches of Indore compost ploughed in. No. 2 plot had some farm rubbish plus 3/8 inch of Indore compost. No. 3 plot was the control and had nothing.
'Since we are eager to get these figures off to you the tabulated weight results of the straw cannot be given. Plot No. I was cut It days ago; plot No. 2 only 2 days ago, and plot No. 3 yesterday. No. 1, therefore, is dry, and Nos. 2 and 3 are still wet. We have given the straw results in similar sized bundles, but No. 1 is the better straw and will make considerably better buffalo fodder (Table 4).
'Once we get all our 30 acres of rice fields fully composted we shall be able to welcome 50 or 60 more lepers here for cleansing. This is not a scientific conclusion according to your usual methods of reckoning, but it is the practical issue as it appeals to us.'
In a subsequent letter dated October 10th, 1935, the Dichpali experience of the Indore Process was summed up as follows:
'Indore compost is one of the material blessings of this life, like steam, electricity and wireless. We simply could not do without it here. It has transformed all our agricultural interests. We have 43 acres under wet cultivation, and most of the land three years ago was of the poorest nature, large patches of it so salty that a white alum-like powder lay on the surface. We have now recovered 28 acres, and on these we are having a bumper crop of rice this year. There have never been such crops grown on the land, at least not for many years. The remaining 15 acres are as before with the rice scraggy and thin. By means of our factory of 30 pits we keep up a supply of compost, but we can never make enough to meet our needs. We are now applying it also on our fields of forage crops with remarkable results. Compost spread over a field to the depth of about one quarter of an inch ensures a crop at least three or four times heavier than otherwise could be obtained.'
Crop results of three plots of rice grown under varying conditions at the Home for Lepers, Dichpali
No. 1 Plot
No. 2 Plot
No. 3 Plot
Amount of land measured for the contrast. All portions had the same cultivation
6,394 sq. ft.
6,394 sq. ft.
6,394 sq. ft.
Amount of seed sown. All the seed sown was the same quality
Amount of rice taken in each case by measure, not weight
Amount of straw in similar sized bundles
The marked response of rice to organic matter in the rice nurseries is well known. The Dichpali results prove that the transplanted crop also responds to humus. In the nurseries the soil conditions are aerobic: after transplanting, the roots of the crops are under water, when the oxygen supply largely depends on the activities of algae. How does humus influence the rice plant in water culture under conditions when the active oxygen must be dissolved in water? Do the roots of rice in the nurseries and also after transplanting exhibit the mycorrhizal relationship? If they do, the explanation of the Dichpali results is simple. If they do not, how then does humus in wet cultivation influence photosynthesis in the green leaf? Nitrification of the organic matter would seem difficult under such conditions for two reasons: (1) the process needs abundant air; (2) the nitrate when formed would undergo excessive dilution by the large volume of water in the rice fields. If, however, the mycorrhizal association occurs in transplanted rice, the Dichpali results explain themselves.
While this book was passing through the press specimens of surface roots of transplanted rice, 116 days from the date of sowing, grown in soil manured with humus, were collected on October 27th, 1939, by Mr. Y. D. Wad in Jhabua State, Central India. They were examined by Dr. Ida Levisohn on December 11th, 1939, whose report reads as follows:
'The stouter laterals of the first order show widespread endotrophic mycorrhizal infection, the mycorrhizal regions being indicated macroscopically by opacity, beading and the absence of root hairs. The active hyphae are of wide diameter; they pass easily through the cell walls and form coils, vesicles and arbuscles; they show the early and later stages of digestion. The resulting mass of granular material appears to be rapidly translocated from the cells.'
There is no doubt that rice is a mycorrhiza-former, a fact which at once explains the remarkable response of this crop to humus and which opens up a number of new lines of investigation. Yield, quality, disease resistance, as well as the nutritive value of the grain will in all probability be found to depend on the efficiency of the mycorrhizal association.
One of the chief problems in market gardening in the open and under glass is the supply of humus. In the past, when horse transport was the rule and large numbers of these animals were kept in the cities, it was the custom, near London for example, for the wagons which brought in the crates of vegetables for the early morning market to take back a load of manure. The introduction of the internal combustion engine changed this: a general shortage of manure resulted. In most cases market gardens are not run in connexion with large mixed farms, so there is no possibility of making these areas self-supporting as regards manure: the essential animals do not exist. The result is that an increasing proportion of the vegetables sold in the cities is raised on artificial manure. In this way a satisfactory yield is possible, but in taste, quality, and keeping properties the product is markedly inferior to the vegetables raised on farm-yard manure.
It is an easy matter to distinguish vegetables raised on NPK. They are tough, leathery, and fibrous: they also lack taste. In marked contrast those grown with humus are tender, brittle, and possess abundant flavour. One of the lessons in dietetics which should be taught to children in every school and institution in the country, and also in every home, should be the difference between vegetables, salads, potatoes, and fruit grown with humus or with artificials. Evidence is accumulating that liability to common ailments like colds, measles, and so forth becomes much less when the vegetables, fruit, potatoes, and other food consumed are raised from fertile soil and eaten fresh.
How is the necessary humus for the high-quality vegetables needed by urban areas to be obtained? Two solutions of the problem are possible.
In the first place, market gardening should, whenever possible, be conducted as a branch of mixed farming with an adequate head of live stock, so that all the waste products, vegetable and animal, of the entire holding can be converted into humus by the Indore Process. The first trial of this system was carried out at the Iceni Nurseries, Surfleet, Lincolnshire. The work commenced in December 1935 and can best be described in Captain Wilson's own words taken from a memorandum he drew up for the members of the British Association who visited his farm on September 4th, 1937:
'The Iceni Estate consists of about 325 acres comprised as follows:
Arable land, &c 225 acres
Permanent grassland 30 acres
Rough wash grazings 35 acres
Land under intensive horticulture 35 acres
'The main idea in the development of the estate has been to prove that even to-day, in certain selected areas of England, it is a commercial proposition to take over land which has been badly farmed, and bring it back to a high state of fertility, employing a large number of persons per acre.
'To this end the estate has been developed as a complete agricultural unit with a proper proportion of live stock, arable land, grass land and horticulture, with the belief that after a few years of proper management the estate can become very nearly, if not entirely, a self-supporting unit, independent of outside supplies of chemical manures, &c., and feeding stuffs, the land being kept in a high state of fertility, which is quite unusual to-day, by
(1) A proper balance of cropping
(2) The conversion of all wheat straw into manure in the crew yards and the utilization of this manure and as much as possible of the waste products of the land for making humus for the soil.
'As regards (2), the method of humus-making which has been employed is known as "The Indore Process", and it has proved successful. The output in 1936 amounted to approximately 700 tons, and in the current year will probably be about 1,000 tons.
'As a result of this utilization of humus, the land under intensive cultivation has already reached a state of independence, and for the last two years no chemicals have been used in the gardens at all either as fertilizers or as sprays for disease and pest control. The only wash which has been used on the fruit trees is one application each winter of lime sulphur, and it is hoped to eliminate this before long.
'The farm land is not yet independent of the purchase of fertilizers, but the amount used has been steadily reduced from 106 tons used in 1932, costing £675, to 40-1/2 tons in the current year, costing £281. Similarly the potato crop, which formerly was sprayed four or five times, is now only sprayed once, and this it is hoped will also be dispensed with before many years when the land has become healthy and in a proper state of fertility.
'Eventually, with a properly balanced crop rotation, there is no doubt in my mind that the same degree of independence can be reached on the farm as has already been attained on my market-garden land.
'The probable cropping will eventually work out as follows:
75 acres potatoes.
75 acres wheat.
25 acres barley, oats, beans and linseed (for stock feeding).
15 acres roots (for stock feeding).
30 acres one year clover and rye-grass leys for feeding with pigs and poultry and cutting for hay, ploughing in the aftermath.
'The live stock carried on the farm at the June returns was as follows:
22 cattle (cows and young stock of my own breeding).
14 horses (including foals).
15 sows (for breeding).
103 other pigs.
120 laying hens (of my own stock).
'And although it is rather early to say, I believe that the above figures may be about right for the size of the farm, with the addition of about 20 cattle for winter yard feeding. This latter importation will be rendered unnecessary in a few years when the number of cattle of my own breeding will have increased.'
Since this memorandum a further advance has been made at Surfleet. The factor which at present limits production on the alluvial soils in the Holland Division of Lincolnshire (in which Captain Wilson's vegetable garden is situated) is undoubtedly soil aeration. These soils pack easily, so the supply of oxygen for the micro-organisms in the soil and for the roots of the crops is frequently interrupted. Sub-soil drainage tends to reduce this adverse factor. During the autumn of 1937 the whole of Captain Wilson's vegetable area was pipe drained. As was expected, the improvement in soil aeration which instantly followed has enabled the crops to obtain the full benefit of humus. Here is a definite example where the establishment of Nature's equilibrium between the soil, the plant, and the animal has resulted in increased crops and in higher quality produce.
Another and perhaps a simpler solution of the organic matter problem in vegetable growing is to make use of the millions of tons of humus in the controlled tips in the neighbourhood of our cities and towns. This subject is discussed in detail in Chapter 8.
A comparison between the cultivation of the vine in the East and the West is interesting in more than one respect. In the Orient this crop is grown mostly for food: in the Occident, including Africa, most of the grapes are made into wine.
The feature of the cultivation of the vine in Asia is the long life of the variety, the universal use of animal manure, and the comparative absence of insect and fungous diseases. Artificial manures, spraying machines, and poison sprays are unknown.
In the West the balance between the area under vines and the number of live stock has been lost: the vine has largely displaced the animal: the shortage of farm-yard manure has been made up by the chemical fertilizer: the life of the variety is short: insect and fungous diseases are universal: the spraying machine and the poison spray are to be seen everywhere: the loss of balance in grape growing has been accompanied by a lowering in the quality of the wine.
During the last three summers, in the course of extensive tours in Provence, a sharp look-out was kept for vineyards in which the appearance of the vines tallied in all respects with those of Central Asia, namely, well-grown plants which looked thoroughly at home, and in which the foliage and young growth possessed real bloom. At last near the village of Jouques in the Department of Bouches du Rhone such vines were found. They had never received any artificials, only animal manure: the vineyard had a good local reputation for the quality of its wine. Arrangements were made with the proprietress to have the active roots examined. They exhibited the mycorrhizal association. The vine is a mycorrhiza- former and therefore humus in the soil is essential for perfect nutrition; the long life of the variety and the absence of disease in Central Asia are at once explained.
In a recent survey of fruit growing in the Western Province of the Union of South Africa, which appeared in the Farmer's Weekly (Bloemfontein) of August 23rd, 1939, Nicholson refers to a local vineyard, on the main road between Somerset West and Stellenbosch, which has taken up the Indore Process:
'Motorists travelling along this road cannot help noticing how healthy this farmer's vineyards look and how orderly is the whole farm. Early this winter I visited it in time to see the huge stacks of manure -- beautiful, finely rotted bush which had been helped to reach that state by being placed in the kraal under the animals. Pigs had played their part too. During the wine-pressing season all the skins of the grapes are fed to the pigs and later returned to the vineyards in the form of manure.'
When the vine growers of Europe realize how much they are losing by an unbalanced agriculture in the shape of the running out of the variety, loss of resistance to disease, and loss of quality in the wine, steps will no doubt be taken by a few of the pioneers to increase the head of live stock, to convert all the available wastes into humus, and to get back to Nature as quickly as possible.
Dymond, G. C. 'Humus in Sugar-cane Agriculture', South African Sugar Technologists, 1938.
Howard, A. 'The Manufacture of Humus by the Indore Process', Journal of the Royal Society of Arts, lxxxiv, 1935, P. 25 and lxxxv, 1936, p. 144.
-- 'Die Erzeugung von Humus nach der Indore-Methode', Der Tropenpflanzer, xxxix, 1936, p. 46.
-- 'The Manufacture of Humus by the Indore Process', Journal of the Ministry of Agriculture, xiv, 1938, p. 431.
-- 'En Busca del Humus', Revista del Instituto de Defensa del éCaf de Costa Rica, vii, 1939, P. 427.
Layzell, S. C. 'The Composting of Sisal Wastes', East African Agricultural Journal, iii, 1937, P 26
Tambe, G. C., and Wad, Y. D. 'Humus-manufacture from Cane-trash', International Sugar Journal, 1935, p. 260.