Defoliation criteria - 200 mmol/m2/s

Just listened to a Growcast episode from 7/18.

The guest mentioned that there is a study showing that an effective criteria for determining whether to defoliate a particular leaf is 200mmol/m2/s. This is because below this level it takes more energy to maintain that leaf than the leaf provides back to the plant.

Just wondering if anyone has seen this study and where I could score a read - sounds like a very interesting idea. Thanks in advance.

 

[420autoflower]

You all might find this interesting.

Nebula's Cannabis Defoliation Experiment - Side-by-side grow journal | Grow Weed Easy

...so it’s time for the second defoliation. Today is Defoliation day: Part 2 Natural tent Defoliated tent (before today’s 2nd defoliation) Here they are after the defoliation tent was plucked...

www.growweedeasy.com

 

[Death The Cultivator]

You all might find this interesting.

Nebula's Cannabis Defoliation Experiment - Side-by-side grow journal | Grow Weed Easy

...so it’s time for the second defoliation. Today is Defoliation day: Part 2 Natural tent Defoliated tent (before today’s 2nd defoliation) Here they are after the defoliation tent was plucked...

www.growweedeasy.com

That is subjective. Nebula's pruning was like non-existent on the non defoliated tent, there was so much bottom pruning that could have been done for desirable buds. At the end the lower third looks like trash. Proper pruning is general with canopy management would have been the ticket versus this old debate on leaf removal.

 

[WildBill]

That is subjective. Nebula's pruning was like non-existent on the non defoliated tent, there was so much bottom pruning that could have been done for desirable buds. At the end the lower third looks like trash. Proper pruning is general with canopy management would have been the ticket versus this old debate on leaf removal.

If you're gonna do a side by side comparison. Keep it in the same tent! That's one huge variable you can remove! Why use clones when they're in two different environments? Might as well used seeds.

 

[Death The Cultivator]

If you're gonna do a side by side comparison. Keep it in the same tent! That's one huge variable you can remove! Why use clones when they're in two different environments? Might as well used seeds.

I don't think the environments were different just because they were in two separate tents with the same equipment. I do agree it would have been preferable though.

The results were so minute, splitting hairs really, that had the first one been pruned properly it would have been "better" but it also produced more larf. Technically the non pruned tent did better.

 

[420autoflower]

I don't think the environments were different just because they were in two separate tents with the same equipment. I do agree it would have been preferable though.

The results were so minute, splitting hairs really, that had the first one been pruned properly it would have been "better" but it also produced more larf. Technically the non pruned tent did better.

Looks to me like the defoliated tent yielded close to 40% more than the naturally grown tent. I’m not into growing airy fluff bud and never include that into my total weight.

 

[WildBill]

I don't think the environments were different just because they were in two separate tents with the same equipment. I do agree it would have been preferable though.

The results were so minute, splitting hairs really, that had the first one been pruned properly it would have been "better" but it also produced more larf. Technically the non pruned tent did better.

"BETTER" is relative.
I like 'quantity' like any person, but I'm here for the best quality. That's what I strive for, no matter what I make from what I grow.

 

[WildBill]

Looks to me like the defoliated tent yielded close to 40% more than the naturally grown tent. I’m not into growing airy fluff bud and never include that into my total weight.

View attachment 1511749

Like has been mentioned, the 'natural' tent could have used better canopy management. It could have vastly improved light penetration with much improved quality of lower flowers.

And naturally, this is totally dependent on the strain. I've grown a couple that just didn't need much if any defol........only opening up type LST.....very minimal.

 

[420autoflower]

Like has been mentioned, the 'natural' tent could have used better canopy management. It could have vastly improved light penetration with much improved quality of lower flowers.

And naturally, this is totally dependent on the strain. I've grown a couple that just didn't need much if any defol........only opening up type LST.....very minimal.

It’s a defoliation comparison so why would he defoliate both tents? No room to do any training so that’s not even a consideration.
Best and most thorough defoliation comparison I’ve ever seen. His environments are close to being identical with the tents being side by side and he’s using basically the same equipment. On top of that he’s growing clones all taken from the same mother.
Doesn’t get any closer than that.

 

[CannabisMingus]

And naturally, this is totally dependent on the strain. I've grown a couple that just didn't need much if any defol........only opening up type LST.....very minimal.

 

[Death The Cultivator]

Looks to me like the defoliated tent yielded close to 40% more than the naturally grown tent. I’m not into growing airy fluff bud and never include that into my total weight.

View attachment 1511749

It’s a defoliation comparison so why would he defoliate both tents? No room to do any training so that’s not even a consideration.
Best and most thorough defoliation comparison I’ve ever seen. His environments are close to being identical with the tents being side by side and he’s using basically the same equipment. On top of that he’s growing clones all taken from the same mother.
Doesn’t get any closer than that.

The first tent could have been bottom pruned without defoliating and would have performed infinitely better than doing nothing. So many unproductive branches that yellowed and looked like hell. Defoliation isn't the same as pruning but I do think any pruning/defol would have improved the yield than doing nothing.

I saw what you meant, I misread the yield and misspoke. It was a better yield overall but still, the other tent didn't even manage the canopy.

@WildBill I saw what you meant, I read that incorrectly lol.