Re: [aroid-l] tubers vs. bulbs vs. corms
>>What is a corm?
>Again according to Hortus III, a corm is "a solid, swollen part of a
>stem, usually subterranean, as the so-called "bulb" of Crocus and
>Think of it this way:
>A tuber is a modified root
>A corm is a modified stem
>A bulb is a modified leaf bud.
You could think of it this way, but according to several of my botany
texts, this is not correct. Both tubers and corms are modified stems, (as
is a rhizome,btw). A potato is indeed a tuber, a modified stem, while a
sweet potato is botanically referred to as a tuberous root, because it is
tuber-like, but being a root, it is not a tuber.
Several years back there was some extended discussion on this listserve
whether or not we were talking about tubers or corms when we were
discussing both Amorphophallus and Arisaema. (It may be that bulb came up
as a possibility also, but that is so obviously incorrect that I don't
really recall.) The consensus wound up favoring tuber as the correct term,
though I was never thoroughly convinced, nor did I get into the discussion
much. At any rate, both these structures, i.e. tubers and corms, are
Jonathan Ertelt, Greenhouse Manager
Department of Biological Sciences
Box 35-1634, Sta. B
Nashville, TN 37235 USA