Cookbooks are full of them, Charlie Dimmock has had her hands on them and, as one has come to expect, the supermarkets have sourced their own plastic versions... We are, of course, talking about 'wild' mushrooms. Not only are we being told how to cook them but there are maps telling us where to go to collect them; what time of year to go looking for them and how much one would have to pay to buy them at market. Chanterelle, cep, parasol, blewit, horse mushroom, field mushroom, beefsteak and the aptly named chicken of the wood are fast becoming familiar names to an ever-increasing number of people. The current demand for 'wild' mushrooms far outstrips the supply – naturally!
The threat to wild mushrooms
Demand drives enterprise and, as we all know, enterprise can be damaging! We already have gangs of mushroom pickers roaming Britain looking for a 'big hit' – a kilo of the wonderful Horn of Plenty can fetch £120 at the London markets! Such is the threat to wild mushroom populations from commercial pickers that English Nature*, in conjunction with the Forestry Commission, have recently published a guide for collectors that positively discourages anyone picking more than 1.5 kilos of wild mushrooms at a time. In certain parts of Britain both private and public landowners have banned the collection of mushrooms from their land.
Producing of 'wild' mushrooms
While all this has been going on, my wife and I have been developing Jac by the Stowl – Humungus Fungus™, a business based around the production of 'wild' mushrooms. We have spent the last three years of our lives developing and testing several systems that facilitate the production of a lot of mushrooms within a very small space. And what is nice about it is that it has been going on in China and Japan for nearly1,100 years, so we didn't have to reinvent the wheel and take the credit all over again! What works in China and Japan can work well in Wales, and, after three years and some fairly difficult moments, we reckon we've cracked it, and we think that the only way forward for us is to promote the technology. So here you go...
Past articles in this magazine have shown how both native and exotic mushrooms can be grown on hardwood logs and recent summer visitors to Ragman's Lane Farm in Gloucestershire will have seen the astounding results that Matt Dunwell has achieved growing shiitake mushrooms on oak logs – results achieved, I may add, by developing his own unique principles of management. Log farming is not the only way to grow edible mushrooms: they can be grown on woodchip, hedge trimmings, sawdust, compost (in its various stages), newspaper, coffee grinds, grass cuttings, leaf litter and, we believe, human waste from compost toilets!
The technology is small-scale, reasonably inexpensive, and organic – and has nothing whatsoever to do with black polytunnels full of horse manure.
Species & Methods
Hardwood Logs - Forget charcoal and rustic chairs this is the only way to use up those small roundwood logs. Growing mushrooms on logs is fairly natural and totally organic (though to get the Soil Association's symbol you have to use wood from an 'organic' woodland or forest). The ideal size for a mushroom log would be no more than 1m (39in) length and 12.5cm (5in) in diameter at base: any bigger and your back will pay a high price for your labour! Logs can be cut as small as 5cm (2in) in diameter, making it an ideal use for neglected coppice woodlands.
Logs are cut in the winter and inoculated with mushroom spawn within a few months of felling. The cost of inoculating logs is extremely variable, but the model below should act as a guide for others to calculate their own costs: 500 x 1m logs x 12cm diameter (90 logs per cubic metre/tonne) = 5.5 tonne of wood.
If you are buying standing wood from a landowner then you should be paying about £6 per tonne – which should be poor quality stuff only. Cutting this wood yourself should take 2 days (conservatively). The same quantity from a local wood-cutter should cost you no more than £60 per tonne cut to your specifications and delivered to your door. If you decide to cut the wood yourself then costs will occur if the wood has to be extracted from the site. If you can get the land owner's permission to inoculate your logs in the woodland and leave them in there to fruit then you are going to make life a lot easier – perhaps making a deal to share the profits? If you own some woodland then there is NO excuse for not using it.
If you do decide to cut the wood yourself then cost your labour at £10 per hour for 8 hours work per day (inclusive of chainsaw and transport costs). The spawn will cost about £300 and the sealing wax, drill bit and inoculating tool will add a further £50 to the overall cost. So, for about £1 per log you have a small log farm, which could, within 2 years, give you 250kg (5cwt) of edible mushrooms, sold at £9 per kilo wholesale. It will take you at least 2 weeks to drill, plug, seal and stack 500 logs, and then there is the management. Oak logs should fruit for at least 5 years and all other hardwoods can be utilised. The following species can be successfully grown on native hardwood logs: shiitake, oyster, enoki, beech oyster, chicken of the wood and nameko. We are continually adding to this list by developing strains from native species, which we collect during the year and test for suitability.
We believe that small farms with a maximum of 5,000 logs will become more popular in the UK and that they could make a fairly reasonable income for the grower. The largest shiitake log farm in Britain has 20,000 logs under management and the owner has claimed publicly that he is not making a profit because of the cost of labour, because of the time invol-ved in management and cheap imports from France, Mexico and Holland. More than 500 logs and you need machinery to assist with management.
Finally, be warned, logs will only fruit twice a year at best so be prepared to move a lot of mushrooms in one go! Our customers want mushrooms every week so we decided to research production on hardwood sawdust, which facilitates weekly production and the demand.
*English Nature: The Wild Mushroom Pickers' Code of Conduct.
Tel: (01733) 455101. Web: www.english-nature.org.uk