Very good question. Some trees, pioneer species as they are called, can
thrive in poor soil because they can survive for some years without
mycorrhizae. I do not know of any that cannot grow because of mycorrhizal
fungi being present. There might be one. One pioneer I can think of is
birch. Birches are planted often in urban areas which the soil is not as
poor as others. Really good question. So where do we draw the line between
poor soil and great soil? In old growth forest I did some soil testing
about the rhizosphere or rhizoplane and found the carbon to nitrogen ratio
to be 27:1. Eastern Hemlock and White Pine. Back to your question. I do
not have the answer. I know some can. On the other hand there are places
where trees won't grow and they have to inoculate with a fungus that will
infect the non-woody roots of the trees and form the organ mycorrhiza. Or
they won't grow.
It sounds like a good question.
I recommend contacting someone in the US Forest Service with a back ground
in tree biology.

let me suggest one off the top of my head.
Dr. Kevin Smith
http://www.fs.fed.us/ne/durham/4505/people/kevcv.html

He did a lot of research with the late Dr. Alex L. Shigo

Remember about mycorrhizae. We cannot inoculate the soil with mycorrhizae.
Mycorrhiza is an organ. You cannot inoculate with an organ. You can
inoculate with a fungus that will infect and then a organ forms.


--
Sincerely,
John A. Keslick, Jr.
Consulting Arborist
http://home.ccil.org/~treeman
and www.treedictionary.com
Beware of so-called tree experts who do not understand tree biology.
Storms, fires, floods, earthquakes, and volcanic eruptions keep reminding us
that we are not the boss.



"CORVIDSTATION61" wrote in
message ...

Hi everyone!
Could anyone tell me if certain plants thrive in poor soil, does that
mean they wont grow very well in good soil? Thanks Mark




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CORVIDSTATION61