permaculture

["Kirby Fry" <peace@totalaccess.net>]

Hello Ute,

>>  There are situations where trees are undesirable because of their
'pumping' action.  <<

I didn't necessarily pick up that the birch's pumping action, and
consequently lowering the water level of the bogs, is inherently a bad
thing.  Can you qualify a bit why it's detrimental?

>>  The slightly drier conditions resulting from this drainage favor the
establishment of (typically) birch trees which are opportunists when it
comes to water supply.  <<

So before the drains were put in the birch didn't stand a chance, and now
with the drains in place the birch are moving in?  It sounds like to me that
if conditions have been created where the birch can grow then they should be
allowed to do so.  Otherwise, we are trying to maintain a system that no
longer suits the topography.

>>  Restoration measures for such peatlands include the removal of the birch
trees and the blocking of drains.  <<

If the drains were blocked and original bog conditions restored then birch
removal seems slightly more appropriate.  However, I bet a lot of trees are
cleared where the drains are not blocked, and original bog conditions are
not restored.  Once again we end up pitting ourselves against what nature
chooses to fill an ecological niche with.

>>  There are also situations where non-native trees can cause damage, such
as eucalyptus plantations in arid regions where they compete with native
vegetation for water.  <<

I'm not necessarily fond of the eucalyptus tree, myself, as it's way
overused in international forestry and extremely flammable.  However, just
about everything on this planet competes for water.  There has got to be
better grounds for eradicating a species than whether or not it's native and
requires water to live.

>>  I guess one has to try and get quite detailed information on the local
ecology and ecosystems and/or observe natural ecosystems well, before one
can judge whether certain trees are beneficial or not in a given situation.
<<

Well, just label me an extremist, but I'm still not convinced that tree
removal is the solution for the scenarios you described.  Thanks for
relating the story, Ute.

Kirby