Does Nature Know Best?

Ron Wenrich woodtick at
Mon Jan 5 01:01:44 EST 1998

dwheeler at wrote:

> I regret to burst the bubble, but I am unconvinced that foresters know
> how to grow trees. Most trees in the US require mycorrhizal fungi to
> survive outside of greenhouse environments. These fungi act as water and
> nutrient gatherers. Studies at Oregon State University have shown that
> terrestrial rooted Western hemlock are 100% mycorrhizal-inoculated in the
> wild. Close observation of trees at a Douglas fir tree farm near Oregon
> City strongly suggests as succession of mycorrhizal fungi as trees
> mature.
> Growing trees (forestry) implies providing trees with necessary
> requirements for their cultivation. So how many species of the several
> thousand mycorrhizal fungi known in the US do foresters know how to grow?
> Of these, how many are used to grow seedling trees?

How would this differ on naturally regenerated sites?  Many hardwoods are regenerated
under a canopy and later released.  There are also quite a few trees which come from
stump sprouts.  These tend to be faster growing since they are taking benefit of the
existing root system (or is it the advanced mycorrhizal association?).  Planting
hardwood seedlings is very rare, unless it is in planting old fields.

> This necessary fungal/plant relationship has been a requirement for
> growing almost all plants since the Devonian (Age of Fishes) time 400
> million years ago. That foresters in general disregard mycorrhizae as
> +beneath them+ is as dramatic a statement as saying they can't see the
> forests for the trees. According to The Primary Source, trees make up
> 30-35% of biomass of either forest or plantation. Fungi make up 52-55%.
> Ignoring fungi in tree cultivation/forestry is similar to corn-stalks
> while growing corn: at this time, you can't have one without the other.

Part of that is in the education of foresters.  Fungi is often regarded as a
pathogen, not a growth enhancer.


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