Suprise! The bushfire approach does work - though it took me a couple
of batches of seed and a few attempts... I finally succeeded in getting
a few seedlings, one of which survived (and is still growing well). It
was a few years ago, but I think I used a few successive small fires of
straw/grass which needs to be very dry to burn properly. I think you
have to avoid slow burning fire as this tends to be very destructive.
Fast burning fires give a *short* (probably intense) burst of heat which
stimulates the seed without roasting them... Terracotta pots are
recommended for this stage!
You could try using an electric heat gun (used for paint stripping, etc.)
instead of fire - the airflow through these guns is fairly small so it
shouldn't blow the contents of your pot out...
Scarification methods *may* work (I haven't tried them). In particular,
pouring boiling water over the seed (not boiling the seed in a saucepan...),
then letting them soak until the swell & sink may be worth a try.
You could experiment with acid-treatments (vinegar maybe?) or
fermentation with a banana or similar, to simulate the 'roo... If you
have hens, you could feed them the seed (don't laugh!, I heard this
worked for one particularly difficult native plant - although the seed
of the plant is targetted for bird dispersal not 'roos...).
+-----------------------------------------------------------------------------+
| John Taylor [Catweasel] | Royal Melbourne Institute of Technology |
| rphjt@minyos.xx.rmit.oz.au | Department of Applied Physics |
| | Melbourne, Victoria, AUSTRALIA |
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