Waterlogging, especially when prolonged will kill most
trees/shrubs, by starving the roots of air, it kills by drowning
trees!
Some trees are specially adapted to cope with this, such as
Willows, Poplars, Alders and Swamp Cypresses. For most it will be
fatal.
If you have existing trees, it is only changes in the
environment that will cause waterlogging, i.e. blocked ditches /
drainage, new sources of water / prolonged wet weather, with no
drainage. We are particularly vulnerable due to the very dry
year last year to pans being created in soils, these are layers
through which the flow of moisture is restricted. This could
alter the nature of your land. Otherwise nature will
have sorted out which trees are suited to your land.
Newly planted trees are especially vulnerable. They are
often planted where there are no trees. It could be that there are
very good reasons why there are not trees in an area, i.e.
waterlogged ground. An expert will help you select trees that
suit your location.
Waterlogged ground can be visible through sitting surface water
(not when only for a few hours after heavy rain, which drains
slowly, when the water persists) or it can be just below the
surface. If you dig a shallow pit and it quickly fills up
with water or you push a cane into the soft soil a short way and it
smells of rotting vegetation, it can indicate you have a very high
water table.
What can you do about this?
Find out if waterlogging is a problem, by observing and
testing.
Plant suitable species for the conditions.
Drain the area
Plant the specimens slightly raised out of the ground, so that
some of the roots can breathe.
Call an expert for advice!