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<pre>I have recently come across some damaged leaves on a young tree and cannot
readily explain the cause, but I suspect some form of herbicide, perhaps
Roundup (glyphosate) may be the culprit. However, this is only a suspicion
based on a process of elimination of other potential causes as I have no
idea what the effects of spray-drift of Roundup onto foliage looks like! Can
anybody describe the effects?

What I have is leaves that are slightly stunted and are curling back along
the length of the leaf, with death of tissue at the tip. This is quite
different to the curling along its length of a desicated leaf, as the leaf
remains quite flat, but curls up and back.

The affected leaves are also a paler green heading towards a yellow shade.
This seems to affect odd trees in a block, not one whole patch so this
pattern leads me to feel that it isn't a nutrition or insect pest problem,
or a waterlogging problem (due mainly to the lack of rain!).

Regards,

Mike Wilson
Hunter Valley.
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<pre>Mike

Roundup (glyphosate) is systemic ie it travels through the entire sytem.
Therefore the entire plant reacts to the element introduced, if Roundup
is used to strength death by dehydration. You can use varying doses for
different effects, I have heard of a greenkeeper using a very weak
solution to retard the growth of bowling greens during periods of
abundant growth. Reaction is also affected by plant activity, during
drought the uptake is reduced.

The leaf symptoms sound like plant stress from any number of factors.

Roger Farquhar

[Non-text portions of this message have been removed]
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<pre>> Mike
>
> Roundup (glyphosate) is systemic ie it travels through the entire sytem.
> Therefore the entire plant reacts to the element introduced, if Roundup
> is used to strength death by dehydration. You can use varying doses for
> different effects, I have heard of a greenkeeper using a very weak
> solution to retard the growth of bowling greens during periods of
> abundant growth. Reaction is also affected by plant activity, during
> drought the uptake is reduced.
>
> The leaf symptoms sound like plant stress from any number of factors.
>
> Roger Farquhar

Roger,

Are you likely to be in the Belford / Rothbury area in the near future, and
would you like to have a look? Quite honestly it has me stumped.

Mike.
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