Mushrooms by Roger Phillips
Probably the best mushroom identification book available. It covers both European and North American species.
It's rather too large to be used as a field guide, but is a must-have as a home reference.
The Easy Edible Mushroom Guide by David Pegler
This is my favourite field guide. The extensive use of graphical icons and abreviated lists make it quick and easy to find key features.
The use of photographs and drawings is surprisingly helpful. You might think that photos would alway be preferable, but the drawings give an idea of the typical that the photo of one specimen never can.
Mushrooms: River Cottage Handbook No.1 by John Wright
This is a very well written mushroom guide. It's a small hardback book so it's very robust and practical as a field guide.
A number of recipes are given in the back of the book. Whilst these are certainly worth having, I'd prefer a separate cookbook and a lighter smaller field guide.
Collins Gem - Mushrooms by Patrick Harding
The small size of this pocket guide means that it covers fewer species than other field guides and doesn't give as much identification detail as other guides.
On the plus side, it's small enough to leave in your bag for those occasions when you come across something unexpectedly and need to double check some point of identification.
River Cottage - Mushroom Magic [DVD]  from River Cottage
Hugh, John and Gill from River Cottage in a DVD mushroom feast. It covers advice on collecting mushrooms as well as how best to cook your hard-earned collection.
A good knife is an essential tool when mushroom hunting. You'll need it for removing fungi from wood, checking for insect lavae and checking flesh colour.
The brush is a useful addition, allowing you to clean new finds before adding them to your basket. This stops dirt getting into the gills of your previous finds.
You really shouldn't try washing mushrooms, they just soak-up the water and go mushy when cooked. Brushing is the best way to deal with dirt on mushrooms.
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