Anthony, Judie and all,
According to Fairley & Moore "Native Plants of the Sydney District",
Casuarina differs from Allocasuarina in "having cones without
protruberances and seed-like winged fruits which are pale and dull (not
dark and shining)".
Anthony Overs' suggestion about whether or not the seeds drop out every
year might also be true, but I do know that Allocasuarina seed cones will
open and the seeds drop out after time, and not just in the event of a
fire. In the Blue Mountains heathlands, A. distyla seeds are a favourite of
the Beautiful Firetail, which they pick out of the opened cones. However
the Glossies always go for the unopened cones.
I also noted from Fairley & Moore that C. glauca (Swamp Oak) cones are
slightly larger than those of C. cunninghamiana (River Oak) - 10-15mm long
by 12mm diam, as opposed to 10mm x 8mm diam. So if Judie's theory about the
cones being too small for the birds to feed efficiently is correct, this
might explain the few records of them feeding on the Swamp Oak. Like
others, I am not aware of any records of Glossy B-Cs feeding on River Oak
seeds, and have never seen chewings of them despite spending quite a lot of
time in River Oak woodland.
Here in the Blue Mountains they feed on A. littoralis, torulosa and distyla.
Carol
---
wrote:
>A while ago a botanist told me that seeds from the cones of the genus
>Casuarina drop out every year, while the seeds from Allocasuarina stay in
>the cone and drop out after a fire event or the like. If this is true (can
>someone confirm this??), then it would be fruitless for glossies to try
>Casuarina cones, except maybe for a brief period.
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