Rapport / Report 2006-12
Auteurs / Authors: Gerben Straatsma
In many EU member states button mushrooms, Agaricus bisporus, are produced as well as the rest product called spent mushroom substrate, SMS. SMS is used in agriculture as a soil conditioner and fertilizer.
Because of risks of surface and ground water contamination with nitrate from agricultural sources, the EU developed legislation to protect these waters, the Nitrate Directive.
The directive states "livestock manure: means waste products excreted by livestock or a mixture of litter and waste products excreted by livestock, even in processed form". The aim of this report was to identify the position of SMS within the scope of the Nitrate Directive, either as "livestock manure"or as another category, not (yet) defined within the Nitrate Directive: compost. For this reason a desks study was performed based on scientific literature.
Studied were:
- The size of the European mushroom industry and the amounts of SMS produced,
- The way in which SMS is produced and its basic composition,
- The stability and maturity of SMS,
- The amounts of nitrogen, specifically the mineral amounts, and the risks for their leaching from SMS,
- Compost standards in an international perspective
- Legislative aspects.
It is concluded that SMS is quite stable and mature. The amounts of mineral nitrogen in SMS are as low as in other composts, much lower than in solid manure. The risk of leaching mineral N from SMS is limited.
The final conclusion is that SMS is a compost.
Financer: Productschap Tuinbouw.
>> Get the full report at Productschap Tuinbouw / Vraag het volledige rapport aan bij Productschap Tuinbouw: www.tuinbouw.nl (PT project 12715)