The law and field mycology:
If the fungi are growing uncultivated on your lawn or field, you are not considered to be in
possession of a Class A drug.
Be aware of the fungi listed in Appendix 12A (below).
If you knowingly collect a fungus listed in Appendix 12A, e.g. Psilocybe semilanceata or Hygrocybe psittacina, you potentially commit an offence of possession. If field identification is possible then it is, of course, unlikely that you would need to take the fungus home for further identification.
If you do not know what the fungus is and have no reason to suspect that it is a controlled drug then it is lawful to collect it and hold it for identification. If it proves to be a species known to contain psilocin or esters of psilocin then it should either be destroyed or forwarded (as soon as possible) to a person who is lawfully able to hold the material. It is important to label material correctly. The label should give the usual information recorded with herbarium specimens (name given to fungus / text used to ID / when / where / who collected it etc.) but with the addition of a statement about the future of the specimen, e.g. ‘Specimen to be forwarded to Royal Botanic Garden, Kew for retention in herbarium’.
If you have collections of the fungi listed in Appendix 12A already in your herbarium then you should destroy the collections or forward them to the custody of a person lawfully able to hold the material.
You may wish to continue to hold Appendix 12A listed fungi as a part of your personal herbarium reference collection. However, an application for an individual licence for this purpose is likely to fail.
Further Information: The Drugs Act 2005 can be found at this URL: http://www.opsi.gov.uk/acts.htm
The Misuse of Drugs (Amendment) (No. 2) Regulations 2005 and the Misuse of Drugs (Designation)(Amendment) Order 2005 can be found at: http://www.hmso.gov.uk/stat.htm
The 2005 Regulations and Order are published by The Stationery Office. Telephone orders / general enquiries 0870 600 5522 or online at: http://www.tso.co.uk/bookshop.
Background and further detail
The following text explains the background to the 2005 amendment of the legislation and gives further detail with regard to exceptions.
Previously existing legislation: The Misuse of Drugs Act 1971: this Act controlled the chemicals inside the mushrooms as a Class A drug rather than the mushrooms themselves. Magic mushrooms were only classified as a Class A drug under that Act if they constituted a preparation or a product containing psilocin or an ester of psilocin. It is a matter of legal interpretation what constitutes a preparation or a product and this had led to uncertainty.