Although fungi can be found at almost any time of year, the best time to see the largest numbers of different species is in the Autumn. There are estimated to be 15,000 species of fungi in Great Britain and distinguishing them takes years of practice and often requires the use of a microscope to look at the structure of spores. These species below can be found in or near woodland areas so look out for them particularly from August to November in Harmers Wood.
If you are foraging and hope to find edible mushrooms ask yourself if you have the necessary field experience as a mushroom hunter. Even experts who have been identifying fungi for decades sometimes stop short of giving a fungus a species name. If botany (my area of expertise) is anything to go by, you will need to have been attempting identifications in the field for 5 to 10 years in the company of more experienced mycologists. This way you will have seen fungi in all their stages of growth and their typical aberrations.