Thermalling with Corn Stalks - CW or CCW?

All,

It is corn havest time here in the upper midwest. After pulling the
corn kernels off the cob, the harvestors grind up the left over corn
stalks and spray them out onto the field for mulch. The lighter corn
stalk leaves sometimes get sucked into thermals and I have seen them
at 7-8K AGL. The first time this happens you get freaked out when
you see something flash by out of the corner of your eye. I, for one,
never expected seeing a corn stalk that high up. Insects? Sure.
Birds of prey and carrion eaters? Yep. Vegetable matter? No way.

Anyway, it is quite a sight. I was chasing one on Sunday trying to
keep it off my wing tip. Had to bank pretty hard and it did out climb
me. No surprise there.

What was surprising is that I noticed it was thermalling the same
direction I was. I guess I never thought about it that a thermal
might be a rotating column of air. I suppose a dust devil is a good
example of a rising and rotating column of air.

So now the questions...

- Do all thermals rotate?
- If they rotate, do they all rotate in the same direction (north of
the equator)? CW or CCW?
- If they all twist the same way, should I turn into thermals with or
against the rotation? (I know, I know, you should turn into the
core ... but this is a hangar flying thought exercise).

Expiring minds want to know.

-- John DeRosa