"Franz Heymann" wrote in message
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"Rod" wrote in message
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"Franz Heymann" wrote in message
...
If you Google on "aspirin rooting" or "salicylic acid rooting" you
will
come across a large number of cases in which aspirin and
willow bark extract are discussed in the context of rooting agents.
Unfortunately all the entries I found are either
qualitatively anecdotal or second-hand reports.

Exactly. We need to see the papers if they exist.
As to rooting powders as found in garden centres - this stuff has
virtually zero shelf life and is therefore almost certainly
worthless at point of sale.

If this is indeed true, could we start a campaign to persuade the
manufacturers to put a "use by" date on the package? Otherwise, as you
say,
we are almost certainly buying pigs in pokes. How am I to know how many
years the stuff has been on the shelves?

On a contrary note: In the case of the powdered materials, how on earth
can
there be any chemical reactions in a powder lying there,quite still? I
notice that in the case of indole-3-acetic acid, which is the most popular
(only?) rooting agent, it has a melting point of 165 deg C. Now, if a
substance is stable enough to survive up to such a temperature *and* is
stable enough to actually melt, and re-solidify, I would have thought that
it would be pretty stable at room temperature.

But not in the presence of water - Garden Centre sundries depts are often
damp. Then from the moment you've dipped your first cuttings in the tub
there is moisture present.

Do you have any reference for your statement that the stuff has a short
shelf-life?

No, but I daresay something on the subject could be found on the internet.
Trying to remember back over nearly 40 years I think it was probably
something I got from college and accepted without too much question. I was
less sceptical back then. However none of my experience of general
propagation (commercially and as a private service gardener) since then has
shown me better quality plants produced quicker or cheaper by the use of
rooting hormones. (Oh yes you often get more massive root systems more
quickly but that doesn't seem to carry through to the finished product, and
Jim has pointed out in the other thread the problems you get finding the
treatment which will give the results you want - his experience in the lab
is pretty much what I found in the nursery.)
Specialist propagators of 'difficult' subjects may find some uses under
their well controlled conditions but I've been out of the nursery trade too
long to have any authoritive information on that.

Rod