Ever seen these ridges in stems?

[nmanpkr]

I was looking closely at some of my branches and noticed there seems to be two types. Some round branches, and some with a ridge like shown in the picture. What's the purpose behind these ridges out of biological curiosity?

A few of my thoughts:

Possibly to channel water to leaf surface onto stomatas. However most branches are on a upward angle and would roll water downward toward new growth, or even down the stalk and into the ground? Possibly making it a defense mechanism against under watering?

The other thing I noticed was new growth seemed to cling to it while forming. You can see in the picture the new leaf almost looks like it was emerging from this point. Maybe it is used to guide new growth? Or maybe the leaf coincidentally grew into it and it's coming out do to pressure.

What are your thoughts?

 

[JuanCarlos]

I believe the round stems are on buds and the stems with channels are on fans. I believe it would be to channel rain and condensation to the stem and therefore the roots of the plant.

 

[AKgramma]

Due to the combination of genetics with these new strains, you are very likely to see odd growth on Cannibus. Enjoy the show!

 

[Greensmurf420]

I have those on my fan leaves as well. Curiosity never got the best of me though.