Although fungi can be found throughout the year in a wide variety of habitats, it is perhaps with woodland (and at this time of year) that most people associate mushrooms and toadstools.

Indeed, many species of fungi have essential symbiotic relationships with trees, both providing and receiving nutrition, in mutuality, to the extent that neither can survive without the other.

This goes further, with particular fungus having an exclusive association with particular species of tree. The Fungi kingdom is thought to contain more than 800,000 species, ranging across over four hundred families. The main body of any fungus comprises a mass of tiny thread-like hypha that network through the soil, trunk of a living tree or in dead wood. These organisms can be thousands of years old and vast in size, dwarfing all other living things on the planet. The terms mushroom and toadstool refer to the fruiting bodies of fungi, serving only to spread the spores of the parent, and are interchangeable (although traditionally ‘mushroom’ has tended to denote edible species and ‘toadstool’ poisonous ones). It is worth stressing here that all species should be treated as suspect unless one is very confident of identifying those that are edible and those that are not.

Fungi can be found in British woodlands throughout the calendar although some are exclusively or most commonly encountered around this time of year and it is these that we will look at here. Within these are represented a number of the fungi orders you would expect to find in Oxfordshire.

Cantharellales (Chantrelles) are highly sought after for the table and are mainly present in oak and beech woodland. In addition to being delicious, they are one of the few fungi that are untroubled by insect infestation and they always occur at ground level. Bright yellow in colour the true Chanterelle is amongst the most prized eaters and most beautiful of fungi. The Horn of plenty is similar in overall appearance, though more inconspicuous, but is dark-brownish and is referred to in places as Black Trumpet. Another good-tasting species.

Agaricales are a large order of fungi and have in their number some of the best-known European species. Honey fungus, otherwise known as Boot-lace fungus, is considered a pest species (forming at the base of trees) and for good reason as causes severe rot and ultimately death in its host. One of the common (and tasty) species to be found in the county and one of our more unusually coloured is Amethyst deceiver, being a most delicate purple-lilac – look for them at BBOWT’s Sydlings Copse and Warburg reserves. Another lilac-coloured, but more robust, fungus is Wood blewit that can be found in both deciduous and coniferous woodlands. This species should not be eaten raw, but, when cooked is a good eater (although some people can be allergic to it). Beech woods are principally where to look, amongst the leaf litter, for the wonderfully named Wood woollyfoot. Fly agaric is possibly the most distinctive toadstool to be found in Oxfordshire, its white-spotted red cap marking it out as poisonous. Sydlings Copse will reveal this species as will its sister reserve, Foxholes. Of all fungi Death cap is the most deadly and the mushroom hunter should even avoid touching it, there is no known antidote. Perhaps thankfully uncommon, it is found in oak woodland. Although edible once cooked, the Blusher is another species best avoided as it otherwise contains toxins (and can easily be confused with the severely toxic Panther cap) – it is common in most types of woodland.

The Cortinariales fungi is another large order and of no culinary interest whatsoever, being inedible at best and poisonous at worst. This order has particular mycorrhizal associations with individual tree species root systems. Birch and conifers support Red-banded webcap, a relatively easily identified by the red-banding on the stem that gives it its name. Peeling oysterling is most commonly found in Ash and Oak woodlands, growing from the branches and trunks of living trees.

Russulales comprise two genera, Brittlegills and Milkcaps, the latter being specifically associated with individual tree species and this can help aid identification. A good number of the order are edible but are generally not considered worth collecting. The sickener has a blood-red cap and is found in coniferous woods. The rather unfairly named Ugly milkcap is common amongst Birch whilst Saffron milkcap is found in coniferous woodland. The previously referred to reserves hold various Brittlegills and Milkcaps as does another BBOWT site, Dry Sandford Pit, where the Woolly milkcap thrives.

The Boletales has in its number some extremely tasty species but also some poisonous ones. Dry Sandford Pit is amongst many birch woodlands around Oxford where one can find Brown birch bolete, a common and often abundant, edible species. It is with Beech and Oak that Penny bun (or Cep) is fond and it is one of the best eating of all fungi species - a decent meal can be had from just one large specimen. Beech woods also support the rare Devil’s bolete, an unpleasant smelling and deadly cousin. False chanterelle looks very similar to the true Chanterelle and can cause severe gastro-intestinal upset. It is found in coniferous woodland and heath-land only.

Amongst the most obvious fungi, Poriales are more commonly known as ‘bracket’ fungi.

These grow on living and dead trees and many are capable of growing to considerable size. Of these the Beefsteak fungus is one of the more easily recognised, its flesh being not dissimilar to raw steak – although the taste can disappoint if it is allowed to dry out. Oyster mushroom, on the other hand, is delicious and common in beech woods including Foxholes. Birch bracket describes adequately the habitat in which it occurs – unfortunate for its host species as its presence will eventually lead to the death of the tree.

Within the order Gasteromycetales are some of the most unusual and interesting-looking species. Collared earthstar looks almost as if it has originated from outside this planet. Associated with Birch, the smallish fruiting bodies need to be searched for amongst the leaf litter. At the other end of the size scale, the Giant puffball can reach the size of a beachball (or bigger) and this species is indeed the largest of all the fruiting fungi but by October most have broken open, releasing billions of spore into the environment. Common earthball is small and ball-shaped, ochre-yellow in colouration on its scaly outer skin that peels back to dark brown interior. The Pestle-shaped puffball is precisely that and the Stump puffball describes its habits – being the only puffball to grow out of the dead stumps of deciduous trees.

In addition to the BBOWT nature reserves mentioned above, check out the following for woodland fungi: Warburg, Rushbed Woods, Whitecross Green Wood, Finemere Wood and Lashford Lane Fen.

Searching out fungi can add much interest and enjoyment to an autumn woodland walk and more so if some of the treasure found end up on the dining table. However, one cannot be over-cautious in warning of the dangers inherent in fungi gathering. As well as ensuring a good field guide is to hand, the responsible mushroom hunter will abide by the code of only collecting a few specimens from that available.

Other trusts that have Oxfordshire woodlands with good fungi populations and which allow public access include The Northmoor Trust, The Wychwood Project and The Woodland Trust.