There are two schools of thought among foragers on the best way to actually “pick” a mushroom. One asserts that fruit bodies should be cut off where they join the ground (or whatever they are growing from) so as not to damage the delicate mycelium below. The other prefers to twist and pull the mushroom from the mycelium. I have heard it argued that this stops the residual stump left by cutting from rotting and “infecting” the mycelium. This is clearly ridiculous as all fungi will rot away eventually if left to their own devices.
I have seen very heated exchanges between the two schools over whose technique is more ecologically sound. The truth is that it makes very little difference to the fungus either way, in the same way that it makes little difference to an apple tree whether you cut or pick its apples. The most important ecological consideration is that the fungi has been allowed to mature to a point where it has distributed most of its spores. A forager is more likely to damage mycelium by compacting or disturbing ground or leaf litter with their feet than by any picking technique. Check out the long-term studies linked in this article, that conclude that that it makes next to no difference – in the species studied (mostly chanterelles). I use italics for this because, as is so often the case, the more you look, the more you see there is to see! Practical experience shows that mycorrhizal fungi (those living in complex symbiosis with vascular plants, eg. chanterelle, cep, hedgehog mushroom) almost always detach cleanly when pulled from their mycelial web, while saprophytic fungi (those rotting down fallen vegetative matter. e.g. wood blewit, clouded agaric, shaggy parasol etc) tend to bring a large clod of mycelium, and plenty of whatever it was feasting on, with them when pulled. So I tend to apply different rules to different species.
On the whole, I generally use the cutting method when picking easily identified species as it minimises disturbance. The accurate identification of some species (notably of the Amanita genus), however, can rely on minute identification features at and just below ground level. In these instances it can be necessary to uproot the entire specimen before covering up the exposed mycelium to keep it from drying out.
I also urge people to stick to the following rules when picking.
1. Don’t pick chanterelles, hedgehog mushrooms, winter chanterelles and other small mushrooms that have a cap diameter less than 2cm. Similarly, ensure boletes, russulas, horse mushrooms, parasols and other larger mushrooms have caps larger than 4cm diameter. These sizes are legal requirements for selling mushrooms on the continent, but are sadly not enforced in the UK.
2. When you are picking a patch of fungi, try to leave the smallest 50%, regardless of size.
3. Where mushrooms are growing in pairs (commonly chanterelles), only pick one.
4. Collect mushrooms into a basket or porous cloth bag that will allow spores to disperse as you move – not a plastic bag.
5. Try to identify mushrooms without picking them. Often accurate identification requires close examination from all angles, but I often see people picking before they engage their brain, needlessly uprooting inedible mushrooms.
6. Dipose of mushroom trimmings and waste in a similar habitat to the one you picked it in.Its best to trim and clean them in situ, which also means dirt and debris doesn’t get lodged in gills or pores, making them much harder to clean when you get them home.
With a few exceptions for highly invasive species such as honey fungus, these rules help support mycological diversity. Fungi perform a crucial job, breaking down debris, nurturing trees and building soils, as well as being a valuable food and home for insects. Following these rules will allow you to harvest on a regular basis with a happy heart and a clear conscience.
For wider information, advice on responsible harvesting and lists of protected plants and fungi click here.