Inflated Bud Sheaths on Cattleya Intermedia

[Anglo]

This Cattleya intermedia has buds developing in a new green sheath and in three older ones that have lost their color. The pale ones grew out green of course, but had faded by the time buds initiated in them. And they were flat before that, but became inflated like little air pillows when the buds appeared. If you squeeze them gently between your fingertips, you can see that they feel like miniature balloons. They also react like balloons when air is displaced within them; a slight compression here results in slight expansion there.

For the sake of observation, I cut a hole in one of them. It immediately collapsed around the buds. In cutting it away after that, I noticed that the material of the deflated sheath was not dry or stiff. It was moist under the outer surface and very flexible.

I have never noticed any inflated Cattleya sheaths before and have never heard of them either. I did a lot of searching on the internet without finding a single reference to this phenomenon. So I’m making up my own theories for now. I’d say the protective properties of an inflated sheath are obvious enough, and can possibly understand a greater need to pump up an older sheath than a young one.

What I don’t understand at all is how it happens. Mainly, how does a Cattleya blow up its sheaths and maintain air pressure in them?

[Gin]

Well all I can think of is the buds give off gas's /moisture which pump them up, a protective measure .. I have seen this before with a couple that bloom through dry sheaths . Gin

[bonsai1504]

I see this all the time. Its a protective device... I think.

[isurus79]

Originally Posted by Anglo

What I don’t understand at all is how it happens. Mainly, how does a Cattleya blow up its sheaths and maintain air pressure in them?

My guess (and its only a guess!) is that there is some gas diffusion (maybe linked to photosynthesis?) on the inside of the sheath, thus slowly blowing it up like a balloon. Basically, as oxygen (or CO2) is being emited from the pores of the plant, those on the inside of the sheath cant escape into the atmosphere and Voila! Balloon sheath! IDK. Maybe.

[Anglo]

Gas diffusion into the sheath from photosynthesis. That sounds like an excellent guess!

Thanks for the responses. This is very interesting to me. I've been used to Catts that bud in green sheaths, rudimentary sheaths or no sheaths at all, so this is something new.

It looks like the balloon sheaths would be good protection, shielding developing buds from damage, maintaining a desired level of humidity, and maybe providing some insulation in fluctuating temperatures. Incubators of a sort.

In any case, they appear to be of critical importance when they occur, based on my one and only observation. The little buds that were in the sheath I removed were bright green and healthy when I cut it off, but they either dried up or were intentionally aborted by the plant. They fell off within three days. Those in the other inflated sheaths are still okay.

Don’t know if there’s any correlation between sheath type and the rate of bud development, but the ones in the green sheath seem to be this plant’s first priority. They have grown at a faster pace than the others. They’ve already broken through the top of the sheath.

[Anglo]

"...previously "empty" dry sheath, start to develop buds, new buds start to increase pressure inside the sheath, so previously non "noticeable" gas trapped inside the sheath start to make some pressure on the sheath walls, them the "balloon" form appear."

I don't think it's that simple, Jan. You see, the newly initiated buds were first observed at about 5 mm. The sheaths, at 5.5 cm and about 1 cm in diameter, were fully inflated at that time. This could not happen as a result of two 5-mm buds adding mass to a minute volume of gas already present in a flat sheath.

If the plant had not breathed air into the sheaths, they could only have expanded in proportion to the mass of the buds, as occurs in green sheaths.

[Cookiemonster]

Now I have to squeeze in here and ask a question! On one of my cattleyas, I do not see any buds yet in the sheaths but they have swollen up like balloons- all three of them, whats going on?
Thanks

[Anglo]

They must be swelling up in anticipation of buds. Mine might have done that too, but I wasn't paying attention until little bud silhouettes were visible.

[Anglo]

Update:

As the buds in the green sheath matured, the ones in the dry sheaths aborted. Meanwhile, another set of buds in a new green sheath are developing very rapidly.

Don't know if this is all according to a logical plan on the part of the plant, such as temporarily holding certain buds in reserve, or part of a failed plan, such as having insufficient energy to support all the buds produced.

I'll post a picture of the flowers in the Cattleya Alliance section.

[Cookiemonster]

Anglo sorry to hear about the aborted flowers, sometimes I have no idea what these plants are doing- my plant still has its puffy sheaths- no buds from what I can see... I will just wait and see... hmmm