i have selected forestry as an optional subject. i have no background of this subject... i have nearly spent two months in preparing this subject... my uncle which is DFP(Divisional Forest Officer) has appeared in CSS.. according to him forestry is the most complicated subject having 35 fields..(and only 100 marks paper) css syllabus contents are forest management, range management, forest statistics, water shed management, forest ecology, forest biology(wild lif management) and so on(in these subjects names of all trees, animals and other micro organisms will include..i have studied it on general level.....is it essential to have an in depth knowledge of all these fields which comprise of minimum nearly 10 to 15 books.. i am very much confused... please give me advice. it will be highly appreciated... please