> Wouldn't limiting light reduce the amount of cloriphil (sp?) produced in
the
> leaf? After all, if you leave your house plants in a dark closet, they
will
> turn pale yellow. Tulip shoots newly poking from the earth are yellow
until
> they get a dose of sun, at which time they turn green. I'd think it'd be
the
> opposite.

Works both ways, actually. Complete shading results in etiolation, or
bleaching - plant doesn't bother trying to make chlorophyll. Probably thinks
it's still underground, and grows leggy instead. If light is too strong, it
will also produce less chlorophyll, as less is needed to capture the
required energy. Look at a shade-tolerant plant like a big-leaf rhododendron
growing in full sun: the exposed leaves tend to be yellowish, where those
deep inside may be full green.

Clever lady, Mother Nature.

-DM