On Sat, 25 Aug 2012 11:43:14 +1000, "Farm1"
wrote:

"David Hare-Scott" wrote in message
...
Brooklyn1 wrote:
"David E. Ross" wrote:

If you really want to kill the ivy, apply Roundup to the foliage
with a sponge or brush, which will avoid damaging the tree on which
it is growing.

That's much too risky. The ivy will quickly draw the Roundup deep
into it's roots where it will be deposited in close proximity to the
tree roots, whereby it will severely damage if not kill the tree.

How do you know this? When a plant is growing strongly roundup is drawn
down into the plant after it is applied to from the leaves, this is
docmentated as part of the way it works and the reason using it on dormant
plants is largely a waste of time . Where did you get the bit about it
crossing from the ivy roots to the tree roots via the soil?

Have you ever used Roundup near roses? It has a very detrimental effect on
roses and it's not as a result of spray drift. I have to say that I tend
towards agreeing with Sheldon on the soil effect.

Roundup is systemic, it enters primarilly through the leaves because
that's obviously what is the only unprotected exposed portion of a
plant where it's absorbed and makes a bee line to the plant's roots,
that's where it kills the plant... even their TV ads scream "My
roots!, My roots!".... cutting off a plant's leaves won't kill most
plants. Once concentrated in the roots one can see the plant dying in
only a short time by observing the part one can see, the leaves will
begin to curl and shrivel as if hit with a blow torch. But
underground plants roots spread and entwine with the roots of nearby
plants and that is where the transfer takes place, it's actually as
though the defolient has taken a short cut, in fact it has. I used to
use Roundup but I don't anymore, I stopped using it about ten years
ago. I was spraying my gravel roadway, about 1,000 ft, to get rid of
the weeds that grew through. It was a nasty job spraying on a hot
sunny day (as recommended), it was expensive for the amount I needed,
but I was willing to make the effort and spend the dollars until one
day I noticed that the deer and other critters were browsing on those
freshly sprayed weeds. I still have a gallon of Roundup concentrate
in my shed but I won't use it, I learned to live with a weedy road,
now I mow it. In fact just last week I hacked down a gigantic rugossa
rose bush growing at the edge of my hedgerow that was sticking out to
grab me as I mowed by. I was very tempted to apply Roundupo to those
stumps but thought better of it knowing I'd take down several plants
nearby and create a large defoliated section, I don't want bald spots,
I'll lose some privacy. And there's a very nice large hickory tree
living right there. I strongly suggest thinking very carefully before
applying Roundup. Even when I sprayed my roadway Roundup killed all
flora for two feet per side wider than I sprayed... it took a few days
longer for its effect to creep.