A new method of mushroom cultivation in north-amerika by J. Gartz,
Integration; journal for mind-moving plants and culture no.4 1993 37-38

Abstract:

In the pacific northwest, during collection of Psilocybe cyanescens, the woody substrate is also
collected in autumn if strong mycelia are visible. These are put on fresh pieces (2-6cm length) of maple
or alder. For the best results a 1:5 ratio of spawn to fresh chips is recommended. The wood chips are
kept in containers or bags with minimal air supply and incubate between 4-20 deg. Celsius. At 4deg.
there are practically no contaminations.

On pure bark the mycelium grows only slowly and without rhizomorphes. It does not occur on the red
cedar mulch.

Next spring freshly cut alder and mabple branches are used for proper cultivation. These pieces are
filled in pits of about 60cm wide and 8-13cm deep, under shadowy shrubs like Rhododendron. The
totally ocergrown wood chips of the prparatory culture are mixed by hand before filling the pit. Then
the material is covered with plastic or cardboard (also a usefull substrate) and watered once a week.
There should be no direct sunlight on the cultures. In september with moderate temperatures or later
the cover is removed and the cultures must be watered, depending on the amount of rain - not flooded.
The first mushrooms appear under humid circumstances in a temperature range of about 8-14 deg.C.
This method is also useful for P. stuntzii and P. baeocystis and for the edible Stropharia rugosoannulata.
P. cyanescens occurs also spantaneously in mulched parks and gardens as the other species.

Comments, from the rest of the article:

Instead of wood chips comercially available mulch (steer-co) works nice, but not cedar mulch.
Fructification ends with the beginning of frost periods but will continue several years. In spring the pits
can be extended with fresh wood-material.

Literature includes (you may have guessed):
Staments & Chilton, the mushroom cultivator, Agarikon Press
Ott & Bigwood, Teonanacatl...., Madrona Publishers, Inc.
Menser, magic mushroom handbook, Homestead Book Company
Stevens & Gee, How to identify and grow psilocybin mushrooms, Sun Magic Publ.