Thermalling with Corn Stalks - CW or CCW?

I saw pretty large corn stalks at cloudbase when I flew from Magalies
Gliding Club near Johannesburg many years ago. I remember meeting
them on each circle - their climb rate was about the same as my
Jantar. I don't recall any obvious rotation and if you calculate the
numbers from the conservation of angular momentum, a rapidly rotating
dust devil slows down as it rises and expands. The best advice is to
look at the cloud overhead and if that is rotating, leave quickly!

I have noted that soaring birds will choose a direction in well-
organized stable thermals, but don't know if this is chosen to
maximize their soaring energy using thermal rotation or just randomly
by the first one up. I have experimented by flying the opposite way
to flocks of soaring birds. They do look annoyed, but eventually give
in and join the bigger bird!

To answer the question of direction of rotation, thermals are too
small to be influenced much by Coriolis force and they rotate randomly
both ways. In fact, it is not uncommon in Arizona to see very large
thermals spin off daughter dust devils on their periphery, these often
spinning in random directions.

Mike