The message
from "anon" contains these words:

Just to clarify, oil of wintergreen - are you saying that this occurs
naturally in composted bark?

Yes. And in reasonable amounts if you choose the right species and
mostly stripped bark. It is pretty impressive to find heaps of bark
steaming in the woods in mid-winter and on a still day the smell of it
lingers in the air.

Well that is probably what it is then. I guess it builds up in the sealed
bag and smells pretty strong when it is first opened. It seems to have
calmed down a bit after several days.

Still, just because this chemical is produced naturally doesn't necessarily
mean that it is harmless to grow vegetables in it. Hopefully the
concentartion is too low to be a concern.

Oil of wintergreen is, or used to be, used as a food flavouring, so I
wouldn't worry about it. The smell may be a salicylate associated with
willow (Salix) bark, which contains small quantities of compounds
similar to aspirin (acetyl-salicylic acid), so nothing to worry about
there, either.

If you have a headache, place tomato on head...

--
Rusty
Open the creaking gate to make a horrid.squeak, then lower the foobar.
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