On Wed, 21 Jan 2004 05:34:24 -0500, "Ray"
wrote in Message-Id:
:

Unless they are old and starting to yellow, brassavolas should not drop
leaves, as they are the entire photosynthesis and water/nutrition storing
elements the plant has.

Agreed. If the plant's leaves are turning yellow and dropping off, I
would guess it's a result of inappropriate irrigation either over or
under. If the plant is mounted as opposed to potted, I would guess it
may not be receiving adequate moisture and/or winter humidity may be
too low. If potted, it may be standing in water. Salt buildup may
also cause leaf drop (and worse). Occasionally a plant receiving
marginal cultural conditions will cannibalize a leaf to provide
sustenance to new growth.

It would aid diagnosis to know if the leaves appear
srhiviled/desicated or if they possess normal turgor, and a
description of the plant's environment and culture would help too.