MYCORRHIZAL INOCULANTS
Well, why not just add mycorrhiza?

If mycorrhiza is so important, why not just 'add it' when planting? Wouldn't that be a wonderful remedy? Mycorrhizologists wryly refer to the idea as 'The Golden Bullet', which at the moment is only a dream [I wrote this in 2001, and it's still true]; a dream that is making a number of hasty entrepreneurs a living and many of their customers disappointed. Still, we need to chase that dream if we are to recover a decent countryside from its ragged remnants.

Anybody can produce industrial quantities of mycorrhizal material using both ecto- and glomalean endomycorrhizal fungi, but only of those species which are amenable to cultivation. If inoculant manufacturers care to provide a list of ingredients - most try to keep such things secret - it can be seen that their constituent fungi are those that are possible, indeed easy to grow: Pisolithus tinctorius, Rhizopogon spp., Glomus mosseae, G. intraradices, G. monosporum and Gigaspora margarita, not those that might be ecologically relevant, for example Scutellospora dipurpurescens, Glomus hoi, Archaeospora trappei and, more significantly, the numerous unidentified and un-named fungi we find in the wild (11 with Bluebell alone at a single Yorkshire site). Incorporation of such cocktails, if they are in good condition, might give an individual seedling tree advantage over others, make your lawn greener or potted glasshouse strawberries grow better. They do not contain fungi that matter in real situations, and there is little to guarantee that the constituents of a commercial inoculant will be viable or usefully active in every, if any, particular ecological application. Soil decompaction and T.L.C. might restore the vigour of a sickly mature tree, but 'magic mycorrhiza dust' placed around its roots will not.

If a tree is not mycorrhizal, it is a dead tree!

We might care to ponder the fact that some of the fungi in commercial inoculants are probably not native to the U.K. (e.g. the entire genus Gigaspora) yet there are no laws to prevent foreign glomalean fungi being introduced into our alien saturated countryside.

A wild community such as woodland is a diverse collection of plants plus all the other organisms which go to make a natural ecosystem. We barely know what the constituent organisms are, let alone how they all interact, and that includes the mycorrhizal fungi and the plants with which they associate. The addition of handfuls of easy-culture fungi to any plant or group of plants has to be a naïve expedient; that is, until we have developed sufficient knowledge and skill to culture and intelligently manipulate the fungi that matter to Bluebell, Wood Anemone, Wavy Hair-grass, Oak and Elm to the benefit of them and all the other wild plants.

This branch of ecology is in its infancy and research effort limited. Let us hope that it does not take too long, because we need to be able to exploit mycorrhiza right now. Apparently, we now have genetically modified, Dutch Elm Disease resistant Elms. That's terrific, but where should we site them in a landscape that has changed since Elm was exterminated? How shall we grow them? They will be grown in nurseries and then planted out by digging holes and bunging them in - in tubes. I could be wrong, but I suspect that that growth will be erratic and many will fail to reach maturity. I wish we had the knowledge to advise growers how it should be done.

The present state of affairs puts one in mind of Gerald Durrell's gloomy observation: "It's as though life had given us a delicately adjusted clock to tell us the time for ever, and without knowing how the hell it works, we at once open up the back and start fiddling around with a blunt screwdriver".