Broad to narrow leaf

[teide]

What actually happens when sativas start out with broad leaves as young plants and end up with narrow? Do the initial broad leaves stay broad, while the later leaves grow narrow, leaving the plant with different looking leaves at top and bottom, or do the broad leaves keep their width while growing longer, thus becoming narrow with age and increased size?

 

[teide]

Guess I'll just have to observe and take measurements myself.

 

[Chuck Jägerschnitzel]

I've noticed the same thing on just about all different plants, the earlier foliage has wider leaf blades than later on, but it seems more pronounced of narrow bladed types.
You can kinda see it here, this is two Honduran-Jamaicans sharing one container, theres a older fan leaf at lower right on the taller plant with broader blades than the the fan leaf front center near the top of the plant, this is last August 3rd, right at the start of flowering

Heres the same plant 3 weeks later with much narrower fan leaves

 

[teide]

Thanks for your reply, chuck. It is easy to see the difference in your photos, yes.
So I guess the earlier fan leaves stay broader, and as new fan leaves emerge, they grow slimmer than the older ones?
The top of the plant in the last photo has slimmer leaves than the top of the plant in the first photo. I wonder what the broad leaves lower down looked like three weeks later, had they slimmed down as well?

 

[wild cat]

Jeśli roślina ma prawidłowy wzrost, to nie jest zaskoczeniem, że ma szersze liście, później cieńsze, prawdopodobnie z tego powodu, aby nie zasłaniać kwiatów. To inteligentna roślina.

 

[teide]

Very good point