John Bryan
Fri, 02 Sep 2005 13:34:55 PDT
Dear Jim:

Thanks for your e-mail. If the buds arise from a corm, as in the example
you site Eleocharis dulcis, (I think this is incorrect, see below) then
for me it is indeed a helophytic geophyte. However I thought this
species was a stolon that becomes tuberous, not a corm. But not all
marsh plants are, Typha and Alsmia are helophytes but not geophytes, but
obviously some plants can be both. A tulip is a geophyte even in a bin
or even in a bag, taking a geophyte out of the ground does not alter the
fact that it is a geophyte. Nor doe putting one into the ground change
it!! I feel your reference to any underground storage tissue derived
from a stem as being a corm, is off the mark, as if this was true, would
not all herbaceous perennial plants become corms? Such would not survive
out of the ground for years, yet corms have this property. No doubt we
will be herded back into line, however I do feel such comments are
valuable and the delete button is never far away! Cheers, John E. Bryan.

Jim McKenney wrote:
> John, I have a problem with the definitions you have cited: they are not
> mutually exclusive. For instance, isn't the water chestnut of Asian cuisine
> (Eleocharis dulcis) properly a helophytic, geophytic corm? (And I hope
> everyone appreciates my punning choice of example).
> We've been through this before: if the term geophytic is purely descriptive,
> then there is no problem in describing something as both a geophyte and a
> helophyte.
> I don't think much good will come of trying to define these terms rigidly. A
> bulb which grows above ground cannot by definition be a geophyte - yet most
> of us would say that it goes against common sense to say that it isn't.
> For that matter, does a tulip bulb on display in a bin in the garden center
> cease to be a geophyte until it is replanted into the ground?
> Furthermore, I see a potential 'escape clause' in any definition which
> includes the word corm. Although there seems to be general agreement about
> what a bulb is, the term corm is much trickier to define. It's easy to
> stretch the definition of a corm to include virtually any dormant
> underground storage structure derived from stem tissue.
> Also, it seems to me that there is something more basic to be observed here.
> Yesterday I ran into a wikipedia entry which included some repartee between
> the original author of a piece and a subsequent reader who asked "shouldn't
> someone change this entry to say..." The original author then reminded his
> critic that everybody was free to give input.
> This is the wiki world: you don't have to ask permission to have an opinion!
> I don't worry about these silly categories people dream up. Even if what you
> have to say is not strictly relevant, it may still be interesting or funny
> or insightful or in some other way valuable.
> If things wander too far, Mary Sue can try to herd us cats back into
> formation.
> Jim McKenney
> Montgomery County, Maryland, USA, USDA zone 7, where I've reclassified my
> Ledebouria socialis into the geophytic ones with bulbs under the soil
> surface, the lithophytic ones with bulbs fully exposed on the gravel mulch,
> the ones I'm going to throw into the pond to make them helophytic ones, and
> finally a potential category for the dead ones which I mistakenly believed
> to be helophytic.
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