Francisco Arqueros IRCHSS Scholar

The uneven process of appropriation by industry of basic mushroom inputs: mushroom compost (part II)    
 
By Francisco Arqueros (Francisco.Arqueros@nuim.ie) 

This article focuses on the events that lead to the development of peak heated (pasteurised) compost in bulk (Phase 2) and spawn run compost in bulk (Phase 3), and the creation of a market for compost in several European countries. These developments, together with the introduction of the low capital bag growing system, accounted for the birth and growth of the satellite growing system in Ireland based on small farms. Next month, I shall deal with the creation and development of the market for compost in Ireland 1979-2007.

 Let us turn first to the development of pasteurisation and spawn running in bulk to understand how seemingly neutral technological developments are not that neutral after all.

Bulk pasteurisation
Bulk composting can be traced back to the 1950s when Ben B. Stoller patented “Bulk Composting and Through Spawning” in the US (The Mushroom Journal, 1989: 129). But bulk composting wasn’t adopted in the US. According to James W. Sinden, only three growers were pasteurising compost in bulk at the end of the 1980s in the US. Yet, in Europe it was becoming the most popular way to carry on composting (TMJ, 1989: 242). We can see in this fact, in the failure to create a market for compost in the US while it succeeded in some European countries, a relation between pasteurising in bulk and the creation of a market for compost. The absolute hegemony of the large mushroom farm inhibited the creation of that market even in the Chester County, Philadelphia, where there has been a significant concentration of mushroom farms since the end of the 1800s (TMJ, August 1989: 242).

The funny thing is that the Knaust brothers, in the US, patented as early as 1934 the two-zone tray growing system with the idea of providing spawn-run compost for sale (Smith, TMJ 1980: 127). Sinden introduced at the end of the 1940s the tray system in Britain, but it didn’t create a market for compost either. Instead it led to the creation of large tray farms making their own compost.

We must, then, trace back modern composting in bulk to 1971, when an Italian company, Agrifung , with a Dutch managing director, Gerard Derks, patented “Three-Phase-One” (Edwards, TMJ 1977: 111) . Derks described at the Mushroom Growers Association (MGA) Conference in 1973 that the three main phases of composting, from fermentation to spawn running, could be carried out indoors in a chamber, all in one. According to Derks, “one of the greatest advantages of the “3 Phase 1” system is the fact that it allows growers to make a pretty cheap incubated compost, ready for being cased in trays, on shelves, or in bags” (TMJ 1984: 61). But he had the Dutch Shelf system in mind when he first thought about this way of composting:

“One night, instead of sleeping, I was thinking of the “3 Phase 1” system producing incubated compost and the new Dutch system with nylon screens for emptying and filling the beds. Before morning I reached the conclusion that it must be possible to combine the two systems. That means to collect the incubated compost from the tunnel, work it on the nets and have an automatic line which adds supplements to it, which also presses the material and then puts the casing layer on and waters it before the nets are moved into the house.”

The first bulk pasteurisation units developed in Italy, with a capacity of 400 tonnes each one, were quite large, and this made difficult to achieve a homogenous pasteurisation. On the other hand, it proved unsuccessful to carry out phase 1 inside a tunnel (Gerrits, TMJ 1988: 471; Gerrits and Van Griensven, TMJ January 1990: 21).

The system was later perfected in Holland in tunnels with a capacity for 80-90 tonnes, and filled up to 2 m high (MacCanna 1984: 53). Phase 1 took place outdoors in the compost yard; phase 2 in a pasteurisation tunnel; and phase 3 in a spawn running tunnel. The two last phases were carried out in two distinct tunnels.

The main question to solve in practice for a good Phase 2 was to get a homogenous as possible resistance to the passage of air throughout the compost. A manometer measured the static pressure of compost to air. Filling had to be very even. If some areas received less air, they could develop weed moulds and diseases. Much more attention to detail was needed in bulk pasteurisation; and the bigger the size of the tunnel, the more difficult to control the process. According to MacCanna (1984: 54) the best way to ensure evenness of pressure in the compost was to ensure that the quality of compost in Phase 1 was also uniform; that non-uniform patches were mixed in with the rest of compost; that the tunnel was filled at the same height; and that there were no breaks or delays when filling the tunnel. He also praised the advantages of bulk pasteurisation (MacCanna 1984: 56):

Probably the most valuable aspect of bulk Phase 2 is the extra control and ease of management possible compared to traditional systems. If the discipline of good and uniform composting is accepted and the tunnel filled evenly, the grower can direct the progress of Phase 2 with little trouble and almost certain success… The technique is also valuable for the bag system and facilitates the transfer of compost from Phase 2 into bags. The elimination of wooden trays, bed boards, etc. from the Phase 2 process is also considered by many to be a worthwhile advance in hygiene.

Vedder (1978: 224-5) could also see the advantages of bulk pasteurisation and spawn running in bulk. In his opinion it was a more rational method of peak-heating and mycelium growth than the peak heating and mycelium growth in trays or shelves. He pointed out that the difference between air and compost temperature would not diverge more than 3ºC in a well-equipped tunnel for peak heating in bulk, while in traditional peak heating tray rooms it can diverge up to 15ºC. Another point was that filling, emptying and spawning could be mechanised with less capital costs. It required only front-loaders and conveyer belts as opposed to the more costly mechanised filling line used in the tray system. According to Tschierpe (TMJ, 1977: 410) the investment in machinery in a bulk composting operation processing 100 tons of phase 1 per week would be £41,000; while in a tray farm it would be between £82,000 and £102,000.

 Finally, the beds in the growing rooms could be filled at their optimum capacity (ie. 90-100 kg per m2), because during Phase 2 and Phase 3 compost shrinks – by  25 % during pasteurisation and 8% during spawn-run (Vedder 1978: 253).
The duration of pasteurisation, on the other hand, doesn’t depend on the method, whether in trays or in bulk, but on the composition of the substrate (Vedder, TMJ 1979: 125). Vedder and Smits (TMJ 1982: 345) considered that it could take from 5 to 7 day, while Vedder (TMJ 1979: 125) had claimed at an earlier stage that it could take between 6 and 9 days.

Bulk spawning
After composting, we have seen that compost must be spawned. Some centuries ago growers made the beds once they considered that composting had been completed, and fertilised them with mushroom mycelium from previous crops. Later, with the one-zone system, growers carried out Phase 2 in trays in the growing room, and when pasteurisation had finished they spawned the compost.

The Sinden-Hauser laboratories in Gossay-Zurich developed the technique of mixed spawning in the 1950s to improve the original method of distributing the spawn over the compost bed and to shorten the period of growth of the mycelium in the compost. Mixed spawning consisted basically in mixing a larger amount of spawn than usual thoroughly with the compost (5 litres per tonne according to Gerrits 1988: 61). To do it correctly, the compost had to be turned again. Therefore, special machines were designed to mix the spawn in working lines in large mechanised two-zone tray farms. In shelf or tray farms on the one zone system small mechanical devices were designed to mix the spawn in the beds after these had been filled. For Vedder (1978: 241-2) the main advantage of mixed spawning was that it shortened the cropping cycle and the mycelium colonised the compost quicker. At the same time, competitive moulds had less chance to develop in the compost. The extra turning, on the other hand, helped to dissipate remaining anhydrous ammonia. Finally, mushrooms spread more evenly on the bed. All this increased yields, and with them, profits. But Vedder also admitted that the working line, in large tray farms, achieved a better mixing because they could reach deeper.

This state of things changed with the development of pasteurisation and spawn running in bulk. The staff would use a simple spawning-device, fitted on the filling machine, to spawn the compost as they filled the spawn running tunnels by using the same belt-system (van As and van Dullemen 1988: 318-319).

According to MacCanna (1984: 128), spawn running takes between 10 and 14 days, and consists in “an incubation period during which the mycelium grows from the grains and permeates the compost.” For Gerrits (1988: 61-2), the compost must be ready for casing and for going in to the growing rooms just after 14 days of spawn running. Vedder and Smits (TMJ 1982: 345) considered a longer period, between 16 and 18 days. They don’t explain why so many or so few days. It could be related to the type of mushroom strains and the composition of the substrate.

 During spawn running the most important thing is to keep the temperature of the compost at 24-25ºC for an optimum growth of the mycelium (MacCanna 1984:128; Gerrits1988: 61-2). The temperature of compost tends to increase because organic matter still brakes down during spawn running, producing heat.
Up until this point, I have briefly described the technical steps that lead to the development of compost as a commodity. But technical progress takes place only in function of its utility to business. That is a constant in the history of the mushroom industry worldwide since this history is linked in all its stages to the world market economy in general, and to the national economies in particular. Now I must turn to the link between money and science. As Gerard Derks (TMJ, 1984: 67) once remarked, “To obtain higher production we need the help of scientists and the various Research Institutes throughout the world. To lower the costs of production we will have to mechanize as much as possible.” I will develop this statement by using the formula “increasing productivity; compressing time; lowering production costs.”

Increasing productivity
There are two main ways to increase the productivity of compost other than through improving mushroom strains (spawn) – to produce a more homogenous substrate during composting and to increase the nutritive value of the substrate by supplementation.

The improvement of composting is generally related to advances in biotechnology. Only in the 1980s it became possible to know, rather than guess, what’s going on during composting. Tests using electron microscopy revealed to researchers how the microbiological process of composting takes place (Wood, Lynch, Rudd-Jones, TMJ 1986: 229-30):

"The straw is invaded via the cuticle and the cut ends and the organisms then proceed to the more resistant parts … [but] microbial attack is not uniform. Even at the end of cropping many straw cell have little or no evidence of microbial degradation. This might indicate that if further, more uniform, degradation could be achieved useful increases in crop yield might be obtained. Manipulation of composting can also be achieved by better control of the composting environment … further fundamental studies of the biochemical and microbiological processes of composting could lead to the production of composts with even greater selectivity and yield … Little is known about the relationship between productivity of a compost and its chemical composition. A better chemical description of compost should provide the information needed to establish criteria for prediction of crop productivity from compost … [and] see if greater conversion of compost [into food] could be achieved."

As recent scientific advances in medicine are rooted in research on biochemical processes, as well as in the food industry in general, so too are advances in composting. The struggle for a more uniform composting degradation, therefore, became the best way to improve the productivity of the compost. Pasteurisation in bulk, as I have shown, proved to be during the 1970s and the 1980 the best way to achieve it. But that wasn’t enough; the same compost producer should also carry out the three different phase of the composting process (fermentation, pasteurisation and spawn-running).

 Fred Atkins, a leading figure of the British mushroom industry from the 1940s to the 1970s, complained about the separation of fermentation and pasteurisation of compost (TMJ 1976: 364): “It is surprising that there are still commercial growers who buy compost ‘ready for the oven’, as it were, leaving the vital pre-Phase-Two preparations and procedures to others over whom they have little control.”

Gerard Derks, around 8 years later (TMJ, 1984: 62), also said, “One of the first mistakes, in various countries, is that growers buy fermented compost and then do their own pasteurisation and incubation.” But then he added, “This may work in a country like Holland, where compost is made according to the rules of the Research Station and the Mushroom Growers School, where every detail is part of public knowledge, and where everything is regularly controlled by the various institutes”.

The unification of the process, however, could take place better on large farms until a market for pasteurised and spawn run compost was created. This is the point when the large farm lost one its advantages in relation to the small ones. Derks’ point is that the higher the scale of production, the easier quality controls which can be implemented and the better the homogeneity of the product which can be achieved. I will deal with the issue of economies of scale in the section about lowering production costs.

Yet, large tray growers couldn’t achieve the same degree of homogeneity pasteurising in trays as they could pasteurising in tunnels. MacCanna (TMJ, 1983: 187, 189) said that the great degree of variation in conditions for pasteurisation in traditional peak-heating chambers (i.e. trays per room, tray depth, compression, homogenous temperature…) made it difficult to standardise composting. But he also added that pasteurisation in bulk was doubly advantageous because “above all, standardization at Phase 2 facilitates standardization of Phase 1 and allows the outstanding deficiencies in a composting programme to be tackled.” Composting, although it can be separated in different phases, is part of a unified process linked up to spawn making and growing.

Another way to improve the productivity of the compost was through supplementation – the equivalent to the use of fertilisers in agriculture. According to Gerrits (1988: 62-66), the idea of supplementing was developed in the early sixties, simultaneously in America and Germany by Sinden and Schisler, 1963, and Lemke, 1963. Supplementation wasn’t perfected, however, until the 1980s, when Gerrits introduced formaldehyde treated soya bean meal (Kohlii, TMJ 1987: 330). The most common products used for supplementation, therefore, derived from soya bean meal, and they could be added at filling just before peak heating, at spawning, or just before casing. After casing it is not suitable because it would disturb the layer of casing.

Gerrits (1988: 66) indicated that, “the increase in production does not come about through the mushrooms becoming larger, but through more pinheads being formed. So, if production increases by 20% through supplementing, 20% more pinheads are formed…” But he warned that a heavier pinning could lower the quality of the harvest since it would “be difficult to remove all mushrooms from the beds with the same quality.”
Supplementation is also easier to carry out when compost is pasteurised and spawned run in bulk. Staff can carry it out at the same time that they fill the tunnels or the mushroom beds. They can just mix it thoroughly with compost by using the belt system and a metering device, or sprinkling it over in the tunnel before emptying.

Compressing time
Agricultural goods must go through a biological production process before they become a finished product ready for consumption. That biological process in agriculture has a centrality  which industry lacks, to the despair of capital investors. Most of the uncertainty in mushroom farming comes from that factor. But it also adds extra time to the production process. That is also true for composting, in the way that the degradation of the compost during fermentation and pasteurisation is a biological process. So too is spawn running, because it depends on the biological growth of mushroom mycelium.

There is an increasingly higher degree of intervention, of human and technical manipulation in composting, but compost makers must wait for fermentation, pasteurisation, and spawn running to take place at a pace not dictated by the machine line, but by the biological process; that is, by nature. Some of the efforts of compost makers and compost researchers have been dedicated to the speeding up of the biological process of degradation of compost. There have been attempts to skip it altogether, but they have not been successful because they are more costly .

 While there is a degree of variability in the time that it takes to carry out pasteurisation and spawn running, the major steps towards the shortening of composting have not been taken in phase 2 and 3. It has been mainly in phase 1. Early in the 1950s, before the mechanisation of the compost yards in Britain, the grower John Peaker (TMJ, 1978: 136) remembered that it used to take 21-28 days to carry out the fermentation of 50 tonnes of horse manure. In the US, at the end of the 1930s, it was normal to ferment the compost between 30 and 40 days before pasteurisation (Stoller, TMJ 1987: 379). John Peaker also remembered that it was in the 1950s when he heard of Sinden’s short compost technique. This method could reduce fermentation to 5 to 7 days and became in time the most widely used internationally (Kohlii, TMJ 1987: 329-330), including Ireland.

There have been attempts to shorten even more composting time. Peter Flegg (TMJ, July 1991: 13), advisor for the British mushroom industry, observed in a visit to Agrifung, early in the 1990s, that the Italian firm was carrying out fermentation in just three days. Gerard Derks, the technical advisor of the company and the guide for the visit, kept the method secret and even made sure no one took any pictures or touched anything. He said, though, that they added solute carbohydrates to the substrate and that they also used a very soft sort of  wheat straw. The final weight of the compost was higher than normal because of a lesser loss of materials, but it didn’t seem to affect yields. I cannot tell how widespread this type of fermentation is today. It is not practiced in Ireland, to my knowledge.
 B.B. Stoller (TMJ, Dec’87: 379) had worked in the 1930s, in the US, on a short fermentation technique which consisted in accelerating the initial decomposition of compost by using a butter-making churn. The compost was quickly revolved with the drum. That was a sort of mechanically-aided composting. They managed to reduce phase 1 to 7 days. The innovation didn’t go beyond the experimental phase.

In 1975, Stoller gave it another try with a ribbon blender. He managed to reduce phase 1 to about 2 hours. He patented his invention in 1979 and set out to improve it. For example, to increase the temperature high enough to kill the nematodes present in the compost, he had to add molasses. He admitted that a large ribbon blender had a high cost, but the saving in areas of concrete for the compost yard and in self-propelled compost turner would compensate for that cost.

Lowering production costs
Composting does not look a difficult operation at first. John Abercrombie’s description was easy enough to follow for any grower with access to horse manure rich in straw. Even a world authority such as Sinden (TMJ, May 1987: 167) claimed as late as 1987 that “there are growers who, without all the elaborate controlling equipment required for Phase II composting in a tunnel, end up with a product consistently yielding a crop equal to that of any grower using tunnels. Maybe the process in shallow layers does promote growth of a combination of organisms and their metabolic products best suited to nutrition of a mushroom.”

Maybe it is so, but it is not a good idea either to generalise from isolated cases. On the one hand, the advantage of composting in bulk must be assessed in relation to the economies of scale that it has contributed to build. On the other hand, we must contextualise Sinden’s statement. He was speaking about the US mushroom industry, where labour is cheap and plentiful, and where the mechanisation of the whole production process, from composting to harvesting, has not been an issue as pressing as in Europe. The best example to draw on is, again, the Dutch mushroom industry, which holds up to the Irish mushroom industry the image of its own future.

In Holland, the Co-operative Dutch Mushroom Growers’ Association (set up in 1953) started to produce compost for its growers with the establishment of a compost centre in 1963, and except for some large growers the majority had stopped making their own compost by 1964 (Vedder 1978: 34, 168; van As and van Dullemen 1988: 309). By the mid 1980s, the Dutch Co-op produced 80 per cent of all mushroom compost used in the Netherlands and the private company Gebroeders Theeuwen most of the remaining 20 per cent (Gerrits 1988: 42).

Vedder gives six advantages for composting on a large scale (1978: 169):
1.    The required raw materials can be centrally purchased in large quantities to assure that high demands can be met at a favourable price.
2.    Manure obtained from many different places, and differing in composition, can be mixed into a more homogeneous product.
3.    Modern machinery can be used profitably in handling huge quantities, resulting in considerable savings.
4.    Personnel working at a centre preparing large quantities of compost will be experienced in handling manure. Also, the results of research and new developments can be put into practice quickly in a large centre.
5.    The mushroom grower does not have to make his own compost, and the capital thus saved can be used for enlarging or improving his own facility.
6.    Individual farms will have fewer problems with flies.

These six points can be summed up in three, which are the basis for the tendency towards concentration and centralisation in compost making: first, the easier mechanisation of composting in economies of scale; second, the easier application of technical knowledge and expertise; thirdly, a higher buying power of, and easier access to, raw materials. Large farms, unlike small ones, can still make their own compost because their size allows them to expel labour through mechanisation, the hiring of experts and access to raw materials. Depending on the size, however, only the largest farms will be able to fully use their machinery.

In relation to the small farms, Van As and van Dullemen (1988: 309) state that “the small scale on which the average Dutch grower operated meant that, making his own compost was a big, unprofitable chore.” That is the other side of the coin: small growers cannot profit from the mechanisation of composting. Gerard Derks (TMJ, 1984: 65) set out the rule for capital investment very adequately: “when the saving of labour equals the cost of depreciation and interest, then the unit is too small to justify the investment.” The key to understanding the advantages of mechanisation, therefore, lies in the labour question, in farming as well as in composting. Vedder only hits the nail in the head when, in passing, he says (1978: 189):
The grower who is able to take advantage of the facilities available in a composting centre, will be able to turn his attention to other matters of importance on his farm. Furthermore, the heaviest and dirtiest work – for which it is becoming increasingly difficult to find labour – will be removed from farm (my italics).

The attention to other matters, which Vedder mentions, has really nothing to do with efficiency per se, but with the scale of the business, which does not allow for mechanisation . If the grower is going to lose money by producing his own compost, then it is better to give it up and to turn exclusively to growing activities, if he has the chance to do it; that is, if there is a market for compost. On the other hand, composting on a large scale, or compost as a commodity, become possible or profitable because the process of composting can be fully mechanised and the heaviest and dirtiest work – for which it is becoming increasingly difficult to find labour – can be removed. It also becomes a possibility to produce cheaper compost.
The advantages of mechanisation, on the other hand, become only tangible beyond a minimum investment limit set by the level the latest technology. As Vedder puts it (1978: 188-9):

"A small turner –onto which the manure is forked by hand– does not save much labour… Real labour savings are achieved only with the large, expensive manure turners which are automatic … [But] Large, automatic turners are not economically profitable for use on the relatively small Dutch farms."

Therefore, the benefits of mechanisation seem to reach only the large farm. But the driving force is still the reduction of labour costs, which is particularly true when wages are “high” and the work process is labour intensive. In the 1950s compost yards in Britain were expanding as the growing operations were, but there was a complete lack of machinery. Growers at that time felt that the most urgent need was “an efficient mechanical manure turner” (Flegg, TMJ 1988: 641). There were some manure turner machines, but they were not self-propelled. The first one, the White Queens composting machine didn’t appear until 1959.

Fred Atkins (TMJ 1978: 118-119) visited a farm in Sweden in 1954 and came across  a “self-propelling, self-feeding turner”, the very first one he had ever seen. He immediately saw the potential labour-saving of that mechanical device. He wrote at the time:

"The high wages paid to labour in Sweden have led this farm to design a manure turner which struck me as being potentially useful to us and perhaps worth manufacturing … Its enormous value to us would be that it would dispense with three or perhaps four of the five men who form our composting team, and do the job in one-tenth the time. Our actual composting costs would be reduced by something like three-quarters. It costs us £3,240 p.a to prepare our compost [Noble Mushrooms Ltd]; we might save £2,430 p.a by the use of the machine."

Still, he wasn’t able to persuade his co-directors to acquire one. It was a matter of time.

The introduction of pasteurisation and spawn running in bulk, apparently, didn’t bring savings in labour time for carrying on composting operations of around 100 tons of phase 1 per week (Tschierpe 1977: 410) in comparison to mechanised tray farm. The productivity of the labour to process compost was at 10 tons per man-hour in operations such as filling and spawning. But I wonder what the figure would be in larger operations, and whether the system of pasteurising in trays could be expanded beyond certain scale. We know of very large composting centres pasteurising and spawn running in bulk in the Netherlands and in Ireland, but there are not composting centres of a similar scale using the tray system.
On the other hand, composting in bulk meant a real saving in machinery, as the figures below indicated for Britain in 1977 for a farm pasteurising 100 tons of phase 1 per week (Tschierpe TMJ, 1977: 410):

Two zone tray system                                        Sterling
One fork tractor                                                12,000
One working line for filling, spawning &casing    50,000-70K
Two high-lifts                                                     20,000
An emptying device                                             6,000
TOTAL                                                             88,000-108K

Tunnel system in a shelf farm                          Sterling
One fork tractor                                                 12,000
One filling device for phase II rooms                  14,500
One filling device for spawn-running rooms       14,500
One filling device for growing rooms                  14,500
7,416 sq m. nets                                                  7,250
Pulling service for nets                                         1,700
Empyting device for nets                                      1,900
TOTAL                                                               66,350

The figures above include machinery that  is used only in growing operations, but it shows the lower capital investment needed for pasteurising and spawn running in bulk.

Another advantage of the tunnel system was its lesser energy requirements in the form of steam for heating during pasteurisation. P. Middlebrook, one of the largest growers in Britain in the 1980s, introduced pasteurisation in tunnels to supply his farms with compost in the season 1978/1979 (Middlebrook, TMJ 1981: 49).  While the consumption of steam was 11,838,100 lb in the season 1977/78, the figure went down to 314,200 lb in 1979/1980. At 0.386p/lb of steam, the saving in energy was remarkable.

Summing up, the mechanisation to carry out composting became a possibility only for companies large enough to afford the cost of the machinery, produce compost in a scale large enough to use up the machinery, and to save more labour than the combined cost of the interest and cost of depreciation of the capital investment. Pasteurisation and spawn running in bulk brought saving in machinery and energy, but their main effect was to open up the possibility of creating economies of scale. The existence of small scale composting in farming enterprises, on the other hand, came to depend on cheap labour, too cheap for the heavy and dirty job of composting in an advanced economy as the Dutch one, or in the creation of a market for compost. In other words, the development of a market for compost in Holland wasn’t just a happy accident. Let us turn now to the link between composting and politics.

The commodification of compost and the revival of the small farm
Last month, I concluded the article by saying that the creation of a market for compost in Ireland in the 1980s brought about the disappearance of the large tray farm in this country. Up until the end of the 1970s, the Irish industry followed closely the British model of large mechanised tray farms making their own compost. After carrying out Phase 1 in the compost yard, staff took the compost to a labour saving machine line where wooden trays were filled and compressed. Then, forklifts took the trays to peak-heating rooms to continue composting. From the peak heating-room, the trays still had to go to spawn-running rooms after passing for a spawning line. From the spawn-running chambers, trays had to undertake another journey to the machine line for casing and, eventually, the trays ended up in the growing rooms.

Long and tedious as the whole process looks, it was fully mechanised by means of the machine line and forklifts. Three operators could process 30 tons of compost per hour (Tschierpe and Hartman, TMJ, 1977: 410). That mechanisation, added to the investment in peak heating and pasteurising room, and the compost yard for Phase 1, including a self-propelled compost turner, and front and back loaders,  was only affordable for big farms. A small enterprise couldn’t justify £20,000 for a small self-propelled compost turner (1981), or a machine line (between £50,000 and £70,000 in 1977), or not even specialised peak heating (£54,000) and spawn running rooms (£96,000) . Rather, a grower and a couple of hired workers would turn the compost manually in the compost yard , fill the trays manually at the end of Phase 1, take the trays to the growing room with the help of a manual forklift, and there carry out pasteurisation, casing, and cropping.

Compost in the latter kind of farms tended to be of inferior quality because, among other reasons, these farms lacked of proper peak heating rooms to carry on composting according to a strict environmental control programme. Phase 1 wasn’t a uniformed process either and that affected the quantity and quality of yields. On the other hand, the volume of capital needed to build a fully mechanised tray farm was out of their reach. In an underdeveloped market for mushrooms, with little competence at international and national levels, small and labour intensive farms could survive because mushrooms were an exotic product and prices were high, but all that changed in the 1970s with the expansion of the industry and the first big crisis of overproduction. In that new state of affairs, small farms were doomed. How then could small farms proliferate in Ireland?

As Tschierpe and Hartman (TMJ, 1977: 408) pointed out, “in industry and agriculture there is a strong trend from smaller to larger units. The reasons for this are well known: better mechanization, fewer skilled people required per unit produced, etc.” In order to explain the counter-tendency of the revival of the small farm in the Irish rural landscape (but also in Holland and Italy), we must take into account the new feature introduced in the mushroom international panorama during the 1970s – the development of pasteurisation and spawn running in bulk , and, with it, the creation of a market for compost, particularly a market first for Phase 2 and later for Phase 3 compost.

Steps in the commodification of compost
The first step in the commodification of compost (i.e. making it with the sole idea of selling it) was the creation of a Phase 1 compost market. In Holland, it happened at an early stage, and at a high scale. As Dutch growers used a one-zone shelf system, when the compost arrived at the farms the operatives filled the shelves in the growing rooms and pasteurised and spawn-run the compost in situ.

In Britain, because large tray farms dominated the industry, the commodification of compost has been one of limited scope. By 1978 only 20 per cent of UK growers used custom compost (Corrin, TMJ, 1978: 6). Hensby Compost Ltd, for example, was set up in 1964 and pioneered the supply of Phase 1 (ready-mix) compost to small and medium farms, but only started to supply farms with Phase 2 compost (in plastic bags) in 1980 (Peaker, TMJ April 1989: 132-3), more or less at the time Irish growers started to get it. By the end of 1981, Hensby was producing around 600 tons per week of Phase 2 (TMJ, 1988: 192).

But for a full commodification of compost in Britain, compost makers had to first break  the resistance of the large tray farms. Unlike in Ireland, it only happened partially. The possibility of mass-producing compost had come into being at the beginning of the 1970s with the commercial development of bulk pasteurisation in tunnels. With this new method, Compost could be produced in higher amounts and at a lower value than with the peak heating in the tray system. It was actually the bag system and the Dutch shelf growing system, particularly popular among small and medium growers, the systems of production that came to the forefront in the next decade, once the mass production of compost in bulk was mastered. That in itself proves that there is a connection between the ways to carry out Phase 2 and the types of growing systems.

Commercial Phase 2 compost freed small and medium growers from the capital investment and labour force required to make top quality compost; highly mechanised mass production made the product cheaper. Therefore, the creation of a market for compost inverted the dismissal of the small and medium mushroom farm, because it took away the main advantage of the big farm, the mechanisation of composting (cropping is still labour intensive). This new development also took place because the production and consumption of mushrooms greatly expanded in Europe thanks to the devaluation of the mushroom commodity . This was also the development that gave way to the creation of the satellite growing system in Ireland. Large tray farms then felt threatened. Two quick examples will illustrate their fear.

In 1977, at the West Midlands/Wales Area meeting of the Mushroom Growers Association (MGA), Claude Head, from the compost maker Bucros Ltd (part of the Darlington group), said that his company was working on a project to supply 2-4 days spawn run blocks of compost as an alternative to ready-mix compost. By this stage Bucros had a weekly production of 1,000 tons of Phase 1. The growers present at the meeting also agreed that this move would eventually liberate peak-heating and spawn-running rooms for growing mushrooms, expanding overnight the productive capacity of the farms without investing a single penny. But these hopes dissipated as soon as growers started to raise the “strong fear that with ‘spawned compost’ cash croppers and surplus building speculators could falsely expand output.” (TMJ, 1977: 80). Claude Head had to assure them that Darlington “under no circumstances” would sell this product outside the existing industry.

G.A. Corrin (TMJ, 1978: 7) warned growers some time later that the introduction of spawned compost was on the verge of ruining large growers in Italy:

When spawned compost was introduced in Italy in the early 70s, the mushroom market quickly became over-supplied, but mainly because established mushroom growers saw quick profits in selling Spawned Compost to peasant farms as cash crops, rather than continuing to grow mushroom themselves. This is a situation not likely to develop in the UK. We are still assessing the economics of Spawned Compost…
From the point of view of large growers, the commodification of spawn compost would “falsely” expand output, over-supply the market, and threaten the economic viability of their farms. On top of that they also believed that it was the work of speculators that eventually would destroy the industry; that is, the established growers. New techniques and with them the objective possibility, later realised, of a general reorganisation of the mushroom supply system spread fear among established growers. Before the commodification of compost, the British mushroom industry had been the particular domain of a handful of large tray growers for nearly 30 years. Only six growers produced 60 per cent of all UK output in 1973 (Corrin, TMJ 1978: 2). But as Corrin foresaw, they didn’t make the same “mistake”, as the Italians did. Yet, they couldn’t stop the development of a market for spawned compost in Ireland and Holland, which later became their main competitors in the British mushroom market, neither did they generally adopted the new developments. That is why throughout the 1980s, we can see in the pages of The Mushroom Journal, organ of the MGA, calls from the modernisers to change the social club way of thinking of the MGA members and to adapt to the new market conditions.

Dr. W.A. Hayes (TMJ 1978: 224), however, didn’t see the development and commodification of spawned compost as a threat. He saw it with the eyes of a researcher, as a further development of the mushroom industry worldwide based on a further division of labour. He probably had in mind the rather old idea of the economic development of whole regions based on small cottiers:

Perhaps of more significance is that this quite simple concept separates the two levels of technology in artificial culture – namely, spawn and substrate manufacture a high technology, and growing a comparatively low technology.

There was here, as well, a chance for underemployed farmers to gain a livelihood, as Cathal MacCanna pointed out (TMJ 1981: 119) speaking about the combination of central composting in bulk and filling and emptying services provided by the compost producer in Holland: “In this way the benefits of sophisticated automation are available to the small grower.” A couple of years later, MacCanna (TMJ 1983: 186) added that “bulk pasteurisation of compost, nowadays [although] looked upon as an integral part of shelf growing, is … practiced extensively [as well] … with low cost plastic units.”

The commodification of compost went a step further with the introduction of spawn running in bulk (phase 3), which although developed at the same time that pasteurisation in bulk took a bit longer to be widely used by growers and still hasn’t completely replaced the market for phase 2, at least not in Ireland. The reason is that Phase 3 compost only brought full advantages to growers on the Dutch shelf system, while in Ireland there are still growers on the bag and block systems.

It is not a surprise, then, that this new development was only “brought to perfection” (Vedder 1978: 225) in the Netherlands, where small and medium growers have dominated the mushroom industry of that country since the end of World War II. A thick network of nearby small and medium farmers, linked through a cooperative structure (the CNC – partly subsidised by the state), arose out of the effort of the Dutch government to develop the old mining area around Limburt, which had entered an economic depression in the late 1940s with the closing down of its mining industry. It is only normal that government and growers directed their priorities towards a way to produce cheap compost in large quantities in a central place. Bulk pasteurisation suited them best when it became a possibility. After the development of spawn running in bulk, small and medium growers could also immediately expand production since growing rooms could be used more intensively. In this way, the Dutch industry achieved an overall output increase of 20-30%, just by moving to bulk pasteurisation and spawn running (MacCanna 1984: 52).

By 1981, 120 farms out of around 800 got spawn-run compost from the CNC, representing 27 per cent of the total growing area in Holland. 30 mushroom farms bulk pasteurised and spawn run their own compost. Only on or above a need of 50 tonnes of compost per week justified the investment in pasteurising and spawn running tunnels (Van Zaayen and Gerrits, TMJ 1982: 115). In Ireland the very first bulk pasteurisation tunnel was built in Kinsealy in 1978 (Staunton 1986: 175), although it was built for research purposes. Commercial compost yards producing in bulk appeared in Wexford, 1979, and Monaghan, 1981. By 1985, Phase 3 accounted for 50 per cent of the whole compost market in Holland (van Griensven 1988: 23). In Britain, however, as late as 1990, P. Middlebrook complained that bulk spawn run compost was not available in the UK market (TMJ, February 1991: 24). In Ireland the production of Phase 3 compost didn’t take place until the mid 1990s.

Integration versus disintegration
The progressive separation or division of labour, between spawn makers, composters and growers also brought about consequences that were not felt at the beginning. The separation between higher and lower technology operations also meant a separation between high capital/low labour intensive industries, on the one hand; and low capital/ high labour intensive industries, on the other hand. As capital tends to flow only into capital intensive industries, the ground was then opened for small businesses in the new low capital growing operations. The division of labour introduced in the mushroom industry by the commodification of compost also created a wider social and economic gap between industry and farming, wherever and whenever small mushroom farming prospered.  
All this means that composting, whether an on-farm or an off-farm process, cannot be dissociated from mushroom growing. In a simplified manner, mushroom growing can be explained as the uninterrupted chain of making the substrate (which includes making spawn and spawning), casing the compost with a layer of peat, marl, etc., actively waiting for the flushes of mushrooms, and cropping and distributing them.
All of that is what constitutes the mushroom industry as a branch of food and agriculture. Mushroom farming, however, is an increasingly downsized process because industrial, commercial, financial and retailing capitals have increasingly appropriated areas traditionally belonging to agriculture. That fact doesn’t need to be a negative one in itself, if it just corresponds to an increasing division of labour related to a constant development of the mushroom industry. It starts to become a negative development when that division of labour reflects power inequalities between workers (the only group present in all the links of the chain), growers, suppliers, marketers, retailers and bankers, among other social actors; when some groups, using their power, exploit economically and impose their politically and social hegemony over the others; and when this distribution of economic and political power hampers the growth of the sectors and enriches some at the expense of others. The first question to understand how this industry works, therefore, is to determine what group (or groups) owns most of the capital and therefore leads the industry.

First, spawn making is separated from mushroom farming; secondly, composting. But it doesn’t happen everywhere in the same way. In the USA, Sylvan Inc had its spawn, composting, and growing operations. Sylvan is an example of vertical integration. However, spawn making is the central operation, where most of Sylvan’s capital is circulating. In Ireland, tray farms in the 1970s controlled all aspects of the process except spawn making. With the structural changes that took place in the 1980s, new growers entering the industry became satellites of both compost making and marketing companies such as Monaghan Mushrooms and Walsh Mushrooms. With the creation of some mushroom villages, some growers even became tenants with no property. That was a short-lived attempt of vertical integration. More recently, we have witnessed in Ireland how Monaghan Mushrooms Ltd has become the largest mushroom grower, apart from being a compost maker and a marketing agent.

We must point out a duality here, two tendencies that coexist in the mushroom industry worldwide as it expands: vertical integration and vertical disintegration. They represent two sides of a process of development that must be explained in its geographical and historical context. In Ireland, for example Monaghan Mushrooms is an example of vertical integration; the rest of the nearly 100 mushroom farms still in operation are the product of the vertical disintegration that took place in the 1980s with the creation of the satellite growing system.
The process of economic development in the market economy, however, is actually better expressed in the concentration and centralisation of capital as a whole, rather than in the formal type of property of the different stages of production. For example, a small grower can own his farm formally but the bank might own its capital, and the marketing group and retailer might control the work process in his farm. Without a doubt, concentration of capital has happened in Ireland chiefly in composting and marketing. The highest level of accumulation of capital if we speak of the production and distribution of food as a whole, however, has taken place in retailing. That will be the theme of an article in the future. The process of concentration and centralisation in composting in Ireland will be the focus of the article next month.

Reference list
Gerrits (1988) ‘Nutrition and Compost’ in van Griensven (ed.) The Cultivation of Mushrooms, Darlingtong Mushroom Laboratories Ltd. and Somycel S.A
MacCanna (1984) Commercial Mushroom Production, Dublin: An Foras Taluntais
van As and van Dullemen (1988) ‘Mechanization and Equipment’ in van Griensven (ed.) The Cultivation of Mushrooms, Darlingtong Mushroom Laboratories Ltd. and Somycel S.A
Vedder, P.J.C. (1978) Modern Mushroom Growing, Educaboek – Culemborg, Netherland; Stanley Thornes – Cheltenham, England
Periodicals
The Mushroom Journal, magazine of the Mushroom Growers Association (MGA) of the UK