great tree book u must own is called,TREES IN BRITAIN by [ROGER PHILIPS]
published by pan books, 500 trees identified by colour photos of leafs, flower, and bark.
lets face it, a trees a tree but look at the leafs,or pine needles or flowers etc a u can tell what type of tree it is, got my copy off ebay as i think its out of print now, its a big book, but best i know, and its idiot proof, [for all us none tree knowers] as all in colour photos for easy identification, ROGER PHILIPS also does a book on MUSHROOMS OF GREAT BRITAIN[PUCKER] and WILD PLANTS OF GREAT BRITAIN, i identified my first pig nut plant threw his book.....
with these books yourl soon know your ash from your ransoms
and lofty wisemans sas survival handbook is by far in my small mind the best survival manual ever printed, a small version is always carried in the small pocket of my ruck