Re Charcoal: My guess would be that it is used in horticulture primarily because of its extremely long life. When used with media components that decompose at a more rapid pace, particles of charcoal will serve to keep pathways for air open a bit longer than they might otherwise. I suppose any other inert filler would do the trick, if not do it better. In my previous post, I did not state that there was NO activation within horticultural charcoal, just that it's limited compared to stuff that has been intentionally activated. That said, I suspect that there is some degree of filtration, sponge-like storage, or as I have also heard, some ion exchange capacity within the stuff, so it does serve to improve and extend the life of organic media.
I grow most of my own collection of potted plants in LECA using the semi-hydroponic culture technique. I have noted that some paphs (those having poor root systems when potted) respond faster if i mix some charcoal with the LECA. That's certainly not because of the mechanical aspects or longevity of the charcoal, so it must be somehow "chemical." Re nanum: That's more related to the size of the blossom, not the plant - in complete contrast to the naming convention used for Phalaenopsis gigantea. Don'tcha just love the consistency of taxonomy? Ray Barkalow - First Rays Orchids - www.firstrays.com Plants, Supplies, Books, Artwork, and Lots of Free Info! .
_______________________________________________ the OrchidGuide Digest (OGD) [EMAIL PROTECTED] http://lists.orchidguide.com/mailman/listinfo/orchids
