Thin shoot out of main marijuana cola

A question from a fellow grower:

why do plants under lights indoors start growing a thin shoot out the top of the main cola near the end of the flower cycle?

Good Question! it is generally related to Sativa. I think it is because Sativa is like indeterminate tomatoes, and will continue to grow forever…

I have asked this question for years, and I have never really gotten a viable explanation; Other than what I just said. As far as I know; This is not an issue, just a hybrid thing. Maybe someone else can shed more light on the subject. Peace