of Florida professor Ed Gilman has a great website with everything you need
to know about woody plants. http://hort.ifas.ufl.edu/woody
Gilman has done extensive studies on what actually happens to roots when
they've been treated differently and he has shown over and over again that
amendments in the planting hole are not necessary and may also cause roots to
circle the area rather than stretch out into the surrounding soil: http://hort.ifas.ufl.edu/woody/amendments.shtml
2001 study: "Effect of nursery production method, irrigation, and inoculation
with mycorrhizae-forming fungi on establishment of Quercus virginiana"
Myth of Collapsing Root Balls: ( http://www.puyallup.wsu.edu/~Linda
Chalker-Scott/Horticultural Myths_files/Myths/B&B root ball.pdf)“Balled
and burlapped root balls must be left intact during transplanting”showed that there was no discernable effect from mycorrhizae inoculations on
newly planted Southern live oak trees.
There are several articles on Linda
Chalker-Scott's Informed Gardener website,
Myth of Fragile Rootshttp://www.puyallup.wsu.edu/~Linda
Chalker-Scott/Horticultural Myths_files/Myths/Fragile roots.pdf) “You
shouldn’t disturb the rootball when transplanting trees and shrubs”
Myth of Soil Amendments: (http://www.puyallup.wsu.edu/~Linda
Chalker-Scott/Horticultural Myths_files/Myths/Amendments.pdf) "When transplanting trees or shrubs into
landscapes, amend the backfill soil with organic matter."
Magazine: Winter 2009 http://hort.ifas.ufl.edu/woody/mycorrhizae.shtml