OK, you guys, wake up. I have a question. Any orchid grower will tell you that
hybrids between Sophronitis & other members of the cattleya alliance almost
always have a quarter to half twist in the leaves. My experience in sewing
leads me to speculate that they didn't fit the front of the leaf to the back
properly. Does anybody have a botanically more correct explanation?
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

Iris Cohen schreef
OK, you guys, wake up. I have a question. Any orchid grower will tell you
that hybrids between Sophronitis & other members of the cattleya alliance
almost always have a quarter to half twist in the leaves. My experience in
sewing leads me to speculate that they didn't fit the front of the leaf to
the back properly. Does anybody have a botanically more correct explanation?
Iris,

+ + +
Sorry not to be able to help here. My math is not up to it.
PvR

Sorry not to be able to help here. My math is not up to it.

I'm missing something. What would math have to do with it?

Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

Sorry not to be able to help here. My math is not up to it.

Iris Cohen schreef
I'm missing something. What would math have to do with it?
Iris,

+ + +
Surely math is the essential tool to describe such things?
PvR

Surely math is the essential tool to describe such things?

You lost me. Here we have a situation where, due to a genetic quirk or
incompatibility, the leaf has a twist. It looks as though the dorsal surface of
the leaf does not quite fit the ventral surface properly. There is something
about the growth process of the leaf which perhaps causes one surface to grow
at a different rate from the other. Maybe my left brain is asleep, but I don't
see where math comes in.

Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

Surely math is the essential tool to describe such things?

Iris Cohen schreef
You lost me. Here we have a situation where, due to a genetic quirk or
incompatibility, the leaf has a twist. It looks as though the dorsal surface
of the leaf does not quite fit the ventral surface properly. There is
something about the growth process of the leaf which perhaps causes one
surface to grow at a different rate from the other. Maybe my left brain is
asleep, but I don't see where math comes in.

Iris,

+ + +
Aren't you doing it yourself?
"one surface to grow at a different rate from the other"
ie two rates, in a curious relationship to each other. Rate of growth is
best expressed in a mathematical formula. Two rates of growth are ...
PvR

In article , Iris Cohen
writes
OK, you guys, wake up. I have a question. Any orchid grower will tell you that
hybrids between Sophronitis & other members of the cattleya alliance almost
always have a quarter to half twist in the leaves. My experience in sewing
leads me to speculate that they didn't fit the front of the leaf to the back
properly. Does anybody have a botanically more correct explanation?

Not that I think I can answer, but do you mean apical vs basal, or
dorsal vs ventral?
--
Stewart Robert Hinsley

Stewart Robert Hinsley schreef
Not that I think I can answer, but do you mean apical vs basal, or
dorsal vs ventral?
--
Stewart Robert Hinsley

+ + +
Remember this is a botany newsgroup:
Animals (and people) have dorsal and ventral sides.
Plants don't. Leafs have adaxial and abaxial surfaces.
PvR

"one surface to grow at a different rate from the other" ie two rates, in a
curious relationship to each other. Rate of growth is best expressed in a
mathematical formula.

I was afraid you were going to say that. Do you think that is what is causing
the twist, that the different sides of the leaf are growing at different rates?
Incidentally, It usually doesn't seem to make any noticeable difference whether
the plant is diploid or polyploid. However, I have one sophro hybrid which is
said to be 4.5n and has leaves like boards. The twist is there, but less
pronounced.

Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

I was afraid you were going to say that.
Iris,

+ + +
Actually I did not say that.
I just said that you said it ;-)
PvR

"Iris Cohen" wrote in message
...
OK, you guys, wake up. I have a question. Any orchid grower will tell you
that
hybrids between Sophronitis & other members of the cattleya alliance
almost
always have a quarter to half twist in the leaves. My experience in sewing
leads me to speculate that they didn't fit the front of the leaf to the
back
properly. Does anybody have a botanically more correct explanation?
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

I don't know either, but I've also seen it in my epiphronitis. Your
speculation seems quite logical but why is another question. And why
sophronitis? I haven't grown a pure sophronitis anything due to our hot
climate, but with our recently upgraded cooling system I plan to soon.
Please post if your searches turn up anything.

I haven't grown a pure sophronitis anything due to our hot climate, but
with our recently upgraded cooling system I plan to soon. Please post if your
searches turn up anything.

I have a warm plant room. The only red minicatt I can grow is Frank's
Valentine, which is not terribly great. I have a magnificent Sophronitis
Arizona cross, Sc. Mini Collins 'Pink Sherbert', HCC/AOS. I was told that S.
Arizona is more heat tolerant than straight S. coccinea.

If you have any rupicolous Laelias, you can tell people you are now growing
Sophronitis. I have a Jungle Elf cross that recently reached maturity &
bloomed. Sure enough, the adult leaves have that same twist.
It's not the Coriolus Effect. My Frank's Valentine has some leaves going one
way & some the other way.
We'd better continue this off the group or in the Orchid Digest, before the
rest of the botanists get after us for talking a foreign language.


Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

Iris Cohen schreef
OK, you guys, wake up. I have a question. Any orchid grower will tell you
that hybrids between Sophronitis & other members of the cattleya alliance
almost always have a quarter to half twist in the leaves. My experience in
sewing leads me to speculate that they didn't fit the front of the leaf to
the back properly. Does anybody have a botanically more correct explanation?
Iris,

+ + +
Sorry not to be able to help here. My math is not up to it.
PvR

Sorry not to be able to help here. My math is not up to it.

Iris Cohen schreef
I'm missing something. What would math have to do with it?
Iris,

+ + +
Surely math is the essential tool to describe such things?
PvR

Surely math is the essential tool to describe such things?

Iris Cohen schreef
You lost me. Here we have a situation where, due to a genetic quirk or
incompatibility, the leaf has a twist. It looks as though the dorsal surface
of the leaf does not quite fit the ventral surface properly. There is
something about the growth process of the leaf which perhaps causes one
surface to grow at a different rate from the other. Maybe my left brain is
asleep, but I don't see where math comes in.

Iris,

+ + +
Aren't you doing it yourself?
"one surface to grow at a different rate from the other"
ie two rates, in a curious relationship to each other. Rate of growth is
best expressed in a mathematical formula. Two rates of growth are ...
PvR