Looking down on it from above

Resin

Really? Can you name two such "professionals"? I would suggest that, like spiral grain or phyllotaxy, twining can be less ambiguously described as ascending to the right or to the left.

Observe the vine as it climbs up its support. If it twines to the right it is clockwise, if it twines to the left it is counter-clockwise. Following are some examples of my own:
Aristolochia-----------twines right
Celastrus--------------twines right
Lonicera---------------twines left
Matelea----------------twines right
Menispermum------------twines right
Wisteria floribunda----twines right
W. frutescens----------twines right
W. venusta-------------twines left
W. sinensis------------twines left

Quote:Experiments indicate that twining "handedness" is largely genetically programmed, with most vines twisting counterclockwise when viewed from the top down. (And no, they don't reverse direction in the Southern Hemisphere.)
I don' know how long this link will be good but; the source is described in a scientific journal as usually reliable.

Have you thought about the fact that a vine growing in the shade will of course reach towards the light (sun) but for half its life will have to turn its back on the light in order to twine? I don't know if I explained that very well but vines have always fascinated me. I looked to see if Chas. Darwin's writings about vines were on line but no luck. Enjoy musing about such things...josh

Did Darwin do a separate book on twining plants or is his work on twining plants included in the movement of plants?

Here is a link that might be useful: The Power of Movement in Plants,

In technical literature, FWIW, you're more likely to see "dextral" and "sinistral" for counterclockwise & clockwise, respectively.

Patrick

Actually, it's the other way around. Dextral = clockwise, sinistral = counterclockwise. That'll teach me not to post when half-asleep...

Patrick Alexander

Albert, Thank you for finding Darwin's work on line...I believe this was the book I remembered. When I first woke up one day and discovered the world of plants (in my twenties!), I devoured every book I could find, not understanding most but just reading, reading. Always have been most interested in the botanists and plant hunters of that era.

To be honest, I probably didn't read the book but just excerpts or articles written about his work. Looking through the Chapter outlines and introduction, there is a good bit about vines, though. My eyesight nowadays limits my reading somewhat...but not my curiosity or interest. so I enjoy your postings and this forum. josh