Live Stoner Chat The science of leaf pruning/defoliation?

[Delps8]

Interesting thread, indeed

The older messages bemoan the lack of research but the simple fact is that the only people with the resources to conduct research that can be put through the peer review process (considered the gold standard despite it being rife with flaws) are very much under the control of the Federal Government. Until cannabis is descheduled, research in the US will be very limited. Despite that, Bugbee at Univ of Utah and Chandra et al at U Miss have produced a lot of valid research on light. Those two "beacons of light" (pun intended) are primarily focused on how cannabis reacts to light and temperature so there's been very little research on growing techniques.

Fortunately, some other countries take a different approach and, in my wandering around the Internet seeking research on cannabis, I came across an interesting paper, attached. I did one pass through it some months ago and highlighted some of the items that were pertinent at the time. The paper has to go into quite some detail to describe the different methods of pruning and that section, as well as some of the details in the outcomes, get a bit thick but they are key to the Conclusion. Given that, it's worth slogging through as much as you can because the best approach according to this document is not "do nothing".

 

[NORB YIPPLS]

I always pluck fan leafs that shade bud sites, it helps air flow too.

Not weed but tomatoes https://www.gardenmyths.com/growing-tomatoes-removing-bottom-leaves/

 

[olbobcat]

Defoliation is key to bigger yields of buds and less larf. Makes trim time easier too. I prefer a bottom up defoliation and never take the fans from top two nodes.

Using these qb96elite v2’s I have to defoliate at the beginning of flower and again after the stretch (week 3)

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Same thing under the qb-120’s

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And man do they get happy after that praying to their sun gods

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I am more of a top-down guy myself. The bottom fans are not shading anything. But I pull them also. I have found that sparser plants grow bigger denser buds.

 

[olbobcat]

Interesting thread, indeed

The older messages bemoan the lack of research but the simple fact is that the only people with the resources to conduct research that can be put through the peer review process (considered the gold standard despite it being rife with flaws) are very much under the control of the Federal Government. Until cannabis is descheduled, research in the US will be very limited. Despite that Bugbee at Univ of Utah and Chandra et al at U Miss have produced a lot of valid research on light. Those two "beacons of light" (pun intended) are primarily focused on how cannabis reacts to light and temperature so there's been very little research on growing techniques.

Fortunately, some other countries take a different approach and, in my wandering around the Internet, seeking research on cannabis, I came across an interesting paper, attached. I did one pass through it some months ago and I highlighted some of the items that were pertinent at the time. The paper has to go into detail to describe the different methods of pruning and that section, as well as some of the details in the outcomes get a bit thick but they are key to the Conclusion. Given that, it's worth slogging through as much as you can because the best approach according to this document is not "do nothing".

I'm going to have to read this 5 times to take it all in but it is the best thing I have seen on this topic.

 

[Delps8]

I'm going to have to read this 5 times to take it all in but it is the best thing I have seen on this topic.

Agreed - good info but it's a slog in a lot of places.