On Tue, 31 May 2005 10:55:52 +0100, VX
wrote:

There are a few trees, mostly ash trees, growing right next to the fence in a
neighbour's garden. The ash trees are not old- about 20 feet high and
apparently seeded in the wrong place and allowed to grow there. Only when I
tried to dig a hole to plant a rose (in my garden) did I realise the extent
of the problem- those roots are seriously invading my garden! My neoighbour
does not want to remove these tress and says she loves them. This could well
be true.

I need to dig down next to the fence and cut them off and then install some
sort of barier to prevent further incursions. it is not a well-maintaned
garden next door and there are brambles and bindweed that I also want to
block off.

As it is I think I'll dig down to the clay (not more than about a foot down)
making a trench along my side of the fence and put some heavy duty black
polythene in there as a barrier, probably folded double. Right next to the
trees I might also insert some leftover laminate flooring planks as they are
mostly synthetic (a veneer of real wood, the rest is fibreglass or similar)
and will be impermeable to roots- just as an extra safeguard- the polythene
could be enough but I might as well be sure.

Any feedback on this- is there anything I've forgotten or not considered or
any warnings of how this can all go horribly wrong?

The only thing I can think of is that if I cut off 40% of a tree's roots on
one side it could possibly die, or without those roots to anchor it on that
side it could get blown over- luckily not in my direction though! And maybe I
should paint the cut-off root surfaces with somethng to seal them.

These 20 foot ash trees are capable of growing to more than 100 feet
and often do!
I have a similar problem with municipal lime trees outside my fence on
a highway verge. I suspect my entire garden has a root network from
them. Certainly every time I dig I find them. I just cut off and pull
out as much as I can. I've got cherry, pear and plum trees of my own
and neither side seems to suffer from the presence of the other and
I've never attacked the roots of the Council trees anywhere like
enough to damage them. I just regard it as occasional 'root pruning'.
I think that trying to stop horizontally spreading shallow tree roots
is doomed to be a constantly losing battle. Obviously they will draw
moisture and nutrients from the soil (that's why they're there) but
they don't seem to affect too much what I grow, apart from making
digging hard work. Add to that the massive autumnal leaf fall and the
prolific spring seedlings from them. Such is gardening life!
Bindweed is probably unblockable. It just goes deeper and deeper and
pops up everywhere. Brambles can be a nuisance too because their
roots throw up suckers often at quite a distance from the parent
plant, and the canes will root where they touch ground. At least ash
trees don't do that.