Extreme Defoliation...

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Rurumo

Rurumo

Well-Known Member
Defoliation definitely works, and even if you set aside the potential yield benefits, some defoliation in a commercial setting is necessary for IPM. But the topic is rightfully controversial, because there is plenty of truth to both sides of the argument. In horticultural terms, defoliation is our attempt to stimulate "overcompensation", which is increased growth rate/yields after defoliation. Overcompensation has been studied for across dozens of plant species and families over the past 35-40 years and it's still controversial for two main reasons. One, overcompensation has proven to be extremely genotype specific across all species that have been studied-it simply doesn't work for all genotypes within a specific species. A lot of these studies have used the major agricultural cash crops like corn, potatoes, and soybeans. And two, scientists have had a hard time replicating the studies that show a large yield increase, even within a genotype known to favor overcompensation. Also, there are many species that show a yield decrease with any amount of defoliation, such as Sunflowers.

We know that it works well for some genotypes, in some crops/plant species. In one famous overcompensation study on a particular genotype of potato, the study found that the highest yields were obtained when 10% of the tubers were damaged by potato moths. So once you have a particular genotype that responds to defoliation with overcompensation, you need to find the exact % of leaf removal that results in the highest yield. Since we have ZERO overcompensation studies in cannabis, any % of leaf removal is completely arbitrary. First of all, your particular genotype may not even respond with overcompensation.....but say it does...In that case, you are just as likely to get maximum yield benefits from a 10% leaf removal as a 90%. In crop studies, every genotype responds differently. I'm not even going to get into the timing of the defoliation, which is a huge topic in and of itself-I'll just say that timing is just as important a factor as % of leaf removal, and "generally" speaking, the later in flower you wait to defoliate, the less likely you are to see a huge benefit from overcompensation (across a wide range of crop species.) But, if overcompensation studies have shown one thing it's that you can't make generalizations across plant species/families on this subject.

To sum it up, no one knows the ideal defoliation % in cannabis to stimulate an optimal overcompensation response because it's genotype specific. The people who take off every single leaf might be right, the people who take off 10% might be right, and the people who don't take off a single leaf might get the highest yields by comparison. It is ALL genotype specific. My personal feelings on the subject is that Cannabis does exhibit an overcompensation response to defoliation, or at least some genotypes do, but anyone who throws out a specific % of leaves to remove, or timeframe, is just being totally arbitrary. Sorry about the long post but I find this to be an interesting subject that always devolves into stupidity when it deserves more attention.
 
M

Markshomegrown

Well-Known Member
rkymtnman said:
i'm not a master grower such as yourself but i don't see the logic in removing leaves, causing stress and then have the plant grow back basically the same leaves you just cut off.

seems to defy the laws of Physics
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If you grow a plant and don't train, topping firm etc, your right no question there.
But as soon as you start training the plant, you need to make adjustments, for example topping once might be OK but if you top 2-3 the canopy becomes very bushy and the lower thinner shoots are stretching for the light, the stretched shoots restrict space, airflow and light getting in the canopy, so you remove these.
This can also cause the plants to grow too many leaves in a small area, the leaves push up agents each other, they start to block light to the other leaves and the lower bud sits can't get any light or airflow but is still pulling water and food from the root mass, you end up with a very thick canopy 2ft thick, solid, and the you lollipop the lower canopy, wouldn't it make more sense to some leaves, so the leaves can be more effective, do you stack solar panels on you roof or spread them out, same kind of thing.
 
Shaded420

Shaded420

Well-Known Member
Rurumo said:
Defoliation definitely works, and even if you set aside the potential yield benefits, some defoliation in a commercial setting is necessary for IPM. But the topic is rightfully controversial, because there is plenty of truth to both sides of the argument. In horticultural terms, defoliation is our attempt to stimulate "overcompensation", which is increased growth rate/yields after defoliation. Overcompensation has been studied for across dozens of plant species and families over the past 35-40 years and it's still controversial for two main reasons. One, overcompensation has proven to be extremely genotype specific across all species that have been studied-it simply doesn't work for all genotypes within a specific species. A lot of these studies have used the major agricultural cash crops like corn, potatoes, and soybeans. And two, scientists have had a hard time replicating the studies that show a large yield increase, even within a genotype known to favor overcompensation. Also, there are many species that show a yield decrease with any amount of defoliation, such as Sunflowers.

We know that it works well for some genotypes, in some crops/plant species. In one famous overcompensation study on a particular genotype of potato, the study found that the highest yields were obtained when 10% of the tubers were damaged by potato moths. So once you have a particular genotype that responds to defoliation with overcompensation, you need to find the exact % of leaf removal that results in the highest yield. Since we have ZERO overcompensation studies in cannabis, any % of leaf removal is completely arbitrary. First of all, your particular genotype may not even respond with overcompensation.....but say it does...In that case, you are just as likely to get maximum yield benefits from a 10% leaf removal as a 90%. In crop studies, every genotype responds differently. I'm not even going to get into the timing of the defoliation, which is a huge topic in and of itself-I'll just say that timing is just as important a factor as % of leaf removal, and "generally" speaking, the later in flower you wait to defoliate, the less likely you are to see a huge benefit from overcompensation (across a wide range of crop species.) But, if overcompensation studies have shown one thing it's that you can't make generalizations across plant species/families on this subject.

To sum it up, no one knows the ideal defoliation % in cannabis to stimulate an optimal overcompensation response because it's genotype specific. The people who take off every single leaf might be right, the people who take off 10% might be right, and the people who don't take off a single leaf might get the highest yields by comparison. It is ALL genotype specific. My personal feelings on the subject is that Cannabis does exhibit an overcompensation response to defoliation, or at least some genotypes do, but anyone who throws out a specific % of leaves to remove, or timeframe, is just being totally arbitrary. Sorry about the long post but I find this to be an interesting subject that always devolves into stupidity when it deserves more attention.
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Quit trying to gaslight Samwell.

+1 for the common sense though
 
Samwell Seed Well

Samwell Seed Well

Well-Known Member
rkymtnman said:
what in that article can you disprove with non bro science?
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Your own articles days their no evidence here or their

"Both sides are absolutely adamant in their conviction about how correct they are, but no matter what either side "thinks" they know... neither one can prove it"


So I guess your contribution is over. You have nothing to offer.

But I know you defoliate, you all do. And when you do. That snap of a fan leaf will snap samwell
 
rkymtnman

rkymtnman

Well-Known Member
Markshomegrown said:
If you grow a plant and don't train, topping firm etc, your right no question there.
But as soon as you start training the plant, you need to make adjustments, for example topping once might be OK but if you top 2-3 the canopy becomes very bushy and the lower thinner shoots are stretching for the light, the stretched shoots restrict space, airflow and light getting in the canopy, so you remove these.
This can also cause the plants to grow too many leaves in a small area, the leaves push up agents each other, they start to block light to the other leaves and the lower bud sits can't get any light or airflow but is still pulling water and food from the root mass, you end up with a very thick canopy 2ft thick, solid, and the you lollipop the lower canopy, wouldn't it make more sense to some leaves, so the leaves can be more effective, do you stack solar panels on you roof or spread them out, same kind of thing.
Click to expand...
so it seems like in nature, plants grow in a christmas tree shape. why do indoor growers change that? to me it seems like we are trying to make up for a loss of light on the sides and bottoms of plants where in nature, sunlight provides that from top to bottom.
 
Samwell Seed Well

Samwell Seed Well

Well-Known Member
rkymtnman said:
this sentence struck me as simplistic but correct:
If you're a Scientist, the same thing is called "Abscission Stress" and the data produced by this group generally shows that any stress in the flower cycle results in lost profits
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Generally is not specific...

And this is just stupid. All growth is stress, cell division is stress , phototropic response is stress... LST, topping, supper cropping all stress responses...you sound moronic when I see you Cherry pick moronic things and being a UB moron protégé makes a lot of sense right now, fuck that racist and anyone who supports him.

Yall can just want my grow, I show up...where's yalls
 
mudballs

mudballs

Well-Known Member
rkymtnman said:
are you familiar with the uncle ben topping method? it's a thread here. he tops at the 2nd true node when the plant gets to a decent height to get 4 main colas.
so you're saying you can achieve the same by removing fan leaves and not actually topping?
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No, im saying i can push hormones. You would actually have to remove the top for the plant to say "oh shit no meristem anymore"
"What i do is more like "lets move some auxin to the lower branches. we dont need it all up here"
 
Samwell Seed Well

Samwell Seed Well

Well-Known Member
rkymtnman said:
more specific than what you can provide as proof though
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No it's general, as stress is many things notnjust the things you want to Cherry pick..and growers do these things selectively to elicit a specific response at that stress of growth...

Keep saying dumb things , gives me narrative to correct
 
rkymtnman

rkymtnman

Well-Known Member
mudballs said:
No, im saying i can push hormones. You would actually have to remove the top for the plant to say "oh shit no meristem anymore"
"What i do is more like "lets move some auxin to the lower branches. we dont need it all up here"
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how do you determine which 4 to remove then? can you post a pic with the leaves you are talking about circled? i'm still not picturing in my head what exactly you are doing.
 
rkymtnman

rkymtnman

Well-Known Member
Samwell Seed Well said:
No it's general, as stress is many things notnjust the things you want to Cherry pick..and growers do these things selectively to elicit a specific response at that stress of growth...

Keep saying dumb things , gives me narrative to correct
Click to expand...
stress is a negative condition. so that diarrhea you just posted i.e. dumb things gives me a narrative to correct
 
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