defoliation question..... anyone familiar with it?
- Thread starter keebo3000
- Start date
Alexander Supertramp
Well-Known Member
Thanks Pat. Not really 'old school' but more like proven horticulture. Really is something to be said about the KISS path. Indoors or out, sometimes it hard to improve on natures proven directions.......
This is some fine bud SuperTramp. Call the Dream Police!!
And I apologize if I have offended you in the past. Seems a while back I jumped the gun a bit and included you in a group of members I shouldnt have in hind sight.
sheik yerbouti
Active Member
Interting article on the subject, not a scientific research project but a good one done by a guy with 30 years experience.
http://www.growweedeasy.com/marijuana-defoliation-tutorial
Until you've tried both ways its stupid to say one way or the other is best.
http://www.growweedeasy.com/marijuana-defoliation-tutorial
Until you've tried both ways its stupid to say one way or the other is best.
Slab
Well-Known Member
Here's the source he gives to support Keef Treez theory of defoliation :
The yield of cowpeas could be increased by judicious defoliation of the older leaves or by topping the growing apices at the onset of flowering. Limited defoliation at the pre-flowering stage did not reduce the yield of beans significantly but severe defoliation at any stage prior to maturity drastically reduced yield. Satisfactory yields of cowpea could be obtained by maintaining only about one-half to two-thirds of the potential leaf-area of the plants, suggesting that a reduction in the number and area of leaves, coupled with a better display of the fewer remaining leaves, could make cowpeas more productive than hitherto.
The yield of cowpeas could be increased by judicious defoliation of the older leaves or by topping the growing apices at the onset of flowering. Limited defoliation at the pre-flowering stage did not reduce the yield of beans significantly but severe defoliation at any stage prior to maturity drastically reduced yield. Satisfactory yields of cowpea could be obtained by maintaining only about one-half to two-thirds of the potential leaf-area of the plants, suggesting that a reduction in the number and area of leaves, coupled with a better display of the fewer remaining leaves, could make cowpeas more productive than hitherto.
sheik yerbouti
Active Member
I think that's the point of defoliation, you need to do it at the right times and the right amount and the taking the proper aged leaves.
I've experienced better results with defoliation and I know some incredible growers that get phenomenal grams per watt yields with defoliation but that was for a certain style of growing. Obviously a blanket statement saying its good or bad is silly because you can provide a zillion scientific studies but until you've tried it for your style and seen the results good or bad you can't say one way or the other. I've seen the results so I know my opinion.
I've experienced better results with defoliation and I know some incredible growers that get phenomenal grams per watt yields with defoliation but that was for a certain style of growing. Obviously a blanket statement saying its good or bad is silly because you can provide a zillion scientific studies but until you've tried it for your style and seen the results good or bad you can't say one way or the other. I've seen the results so I know my opinion.
PJ Diaz
Well-Known Member
True. It depends on what leaves taken when in what quantities based on a specific growing style combined with plant genetics.
For the full text on the cowpea study, look here: http://pdf.usaid.gov/pdf_docs/PNAAT203.pdf
In same cases they got less yield and in other cases more yield, depending on the specifics noted above.
For the full text on the cowpea study, look here: http://pdf.usaid.gov/pdf_docs/PNAAT203.pdf
In same cases they got less yield and in other cases more yield, depending on the specifics noted above.
Bud Brewer
Well-Known Member
Here are some studies
Here Is a study Compensatory growth responses to defoliation and light availability in two native Mexican woody plant species
http://journals.cambridge.org/action...66467409990514
Defoliation, often caused by herbivory, is a common cause of biomass loss for plants that can affect current and future growth and reproduction. There are three
models that predict contrasting compensatory growth responses of plants to herbivory and resource availability: (1) Growth rate model, (2) Compensatory continuum
hypothesis and (3) Limiting resource model. The predictions of these three models were tested on the tree Brosimum alicastrum and the liana Vitis tiliifolia.
Seedlings were subjected to three levels of experimental defoliation (0%, 50% and 90% leaf removal) along a light resource gradient (1%, 9% and 65% of full sun).
In both species, defoliation significantly increased leaf production rate and relative growth rate of leaf area, but not of biomass.
Net assimilation rate was the strongest driver of biomass growth in both species, but leaf area ratio and specific leaf area were also important in B. alicastrum.
Compensatory responses of leaf area growth in B. alicastrum were significantly greater in higher than lower light availability, consistent with the compensatory
continuum hypothesis predictions, but in contrast to the growth rate model predictions. The limiting resource model offered an explanation for all possible
experimental outcomes by directly considering the effects of environmental differences in resource availability.
One more http://journals.cambridge.org/action...1447970002353X
Effects of Artificial Defoliation (Simulating Pest Damage) on Varieties of Upland Rice
W. E. Taylora1
a1 Njala University College, University of Sierra Leone, P. M. B. Freetown
Abstract
Artificial defoliation was used to simulate grazing by cutting-grass or cane-rat (Thryonomys swinderianus), on three rices with durations of 110115, 130135
and 140145 days respectively, defoliated before, during and soon after tillering by removing leaves to half, two-thirds and the total height of the plants.
All varieties showed marked compensatory growth, resulting in increased tillering and yield, especially when defoliated during tillering, but yield fell when
foliage was removed after tillering, especially with shorter duration rice. Defoliation to half the height of the plant during tillering had the most beneficial
effect, whereas removal of all leaves to soil level after the tillering stage had the most adverse effect.
And another it produces more corn & double the cotton in dry conditions http://journals.cambridge.org/action...14479703001534
EXPERIMENTAL ASSESSMENT OF THE IMPACT OF DEFOLIATION ON GROWTH AND PRODUCTION OF WATER-STRESSED MAIZE AND COTTON PLANTS
Z. YANG a1c1 and D. J. MIDMORE a1
a1 Plant Sciences Group, School of Biological and Environmental Sciences Central Queensland University, Rockhampton Qld 4702, Australia
Article author query
yang z [PubMed][Google Scholar]
midmore d [PubMed][Google Scholar]
Abstract
In this study, different levels of defoliation were imposed on a determinate species (maize) and a relatively indeterminate species (cotton).
The aim was to quantify the effects of defoliation on plant growth and production, under either optimum or water-stressed conditions. Under well-watered conditions,
33% defoliation twice (conducted 28 and 35 days after emergence) resulted in a 16% reduction in grain yield of maize while 67% defoliation once
(conducted 28 days after emergence) had no significant effect on yield. Under water stress, the grain yields of maize plants with 33% (twice) and 67% defoliation
were 13.5% and 25% greater than that of non-defoliated control plants, respectively. For cotton, the reproductive yields (seed and lint) with 33% and 67% defoliation
(conducted 43 days after emergence) were reduced, under well-watered conditions, by 28% and 37% of that of the non-defoliated control, respectively.
Defoliated cotton plants lost less fruiting forms (squares and young bolls) than non-defoliated plants during water stress. Therefore, under water stress the
harvestable product of cotton plants with 67% defoliation was double that of non-defoliated control plants. In non-defoliated cotton plants, a second flush of
flowering after release from water-stress permitted further compensatory fruit set and boll harvest. Defoliated plants did not show such levels of compensation.
Defoliation significantly reduced water use by maize and cotton. The relative yield advantage of defoliated plants under water-stress conditions can be attributed
to defoliation-induced improvement in water status as reflected in measures of photosynthetic rate and stomatal conductance. Under anticipated drought stress,
defoliation could be an important management practice to reduce drought-induced yield decrease, but this needs to be tested under field conditions.
(Accepted August 5 2003)
Just one more with corn http://journals.cambridge.org/action...21859600062043
Defoliation studies in hybrid maize: II. Dry-matter accumulation, LAI, silking and yield components*
R. P. Singha1 and K. P. P. Naira1
a1 Department of Agronomy, G. B. Pant University of Agriculture and Technology, Pantnagar, India
SUMMARY
Data are presented from an experiment made in two crop seasons, to examine the effects of plant density and degree of defoliation at different stages of growth
in maize at Pantnagar, India, on the dry-matter accumulation in different plant parts, leaf area index (LAI), time of silking and grain yield components.
Different patterns of dry-matter accumulation in various plant parts was observed. Silking was delayed by increasing plant density. Defoliation (even partial)
at the 16th fully expanded leaf stage resulted in substantial reduction in LAI and such yield components as number of ears, ear length, ear diameter and
1000-grain weight. On the other hand, partial defoliation done at the 10th fully expanded leaf stage to simulate an erectophile canopy led to yield increases
even under high plant density (90000 plants/ha) in the Kharif (rainy season), mainly through an increase in number of ears, 1000-grain weight and grain to stover
ratio coupled with a reduction in barrenness and percentage of lodging. It is suggested that an increase in the photosynthetic efficiency per unit area of leaf
resulting from the erectophile canopy is the reason for these effects.
(Received December 18 1974)
http://www.actahort.org/books/218/218_10.htm
LEAF YIELD RESPONSE OF ETHIOPIAN MUSTARD (BRASSICA CARINATA A BR) SELECTIONS TO DEFOLIATION REGIMES
Authors: N.A. Mnzava, W.W. Msikita
Abstract:
The influence of leaf harvest frequency (weekly or bi-weekly) and amount of leaf removal (10%, 50% or 75%) on total yield of three local Ethiopian mustard
selections 'CRRS-V', 'CRRS-II' and 'Mulio Giant' were studied during two consecutive winter seasons in the field. The amount of leaves removed at each harvest
rather than harvest frequency significantly affected total yield which was test cultivar-dependent. Yield increased with defoliation rate to an optimum at 27 t
ha-1 for 'Mulio Giant', and 40 t ha-1 in 'CRRS-II' under either a 50% weekly or 75% bi-weekly harvest frequency, while 'CRRS-V' attained 55 t ha-1 under a
50% bi-weekly harvest frequency. More frequent and intense defoliation tended to prolong the vegetative phase in all cultivars. The physiological consequences
of defoliation on earliness to flower and compensatory growth in relation to yield variation in vegetable mustard is discussed.
This showed no loss in grain weight but increased leaf production and photosynthesis http://www.ncbi.nlm.nih.gov/pubmed/19090232?dopt=Abstract
Effects of timing and defoliation intensity on growth, yield and gas exchange rate of wheat grown under well-watered and drought conditions.
Ahmadi A, Joudi M.
Source
Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Tehran, Karaj, Iran.
Abstract
The aim of this research was to determine the effects of timing and intensity of source reduction on grain yield of wheat under well-watered and drought stress
conditions. A field experiment was conducted at the research farm of the Agriculture College, University of Tehran, Karaj, in 2003-2004. Drought stress was
imposed when plants were at the second node stage by withholding watering and plants were re-irrigated when they showed signs of wilting or leaf rolling,
particularly during the morning. Various intensities of leaf defoliation were performed at three growth stages: booting, anthesis and 20 days after anthesis.
Flag leaf gas exchange parameters as well as chlorophyll content measurements were made 20 days after defoliation at each growth stage. Generally leaf removal
appeared to stimulate an increase of net photosynthesis rate (p(n)) and stomatal conductance (g(s)) of the remaining flag leaf. With leaf removal, stability of
the flag leaf chlorophyll content tended to increase. Neither grain yield, nor protein content were affected by defoliation. Interestingly, even removal of all
leaves at anthesis stage did not reduce grain yield and grain protein significantly. Increased remobilization of stored photoassimilate, decreased maintenance
respiration by source reduction and therefore enhanced photoassimilate partitioning toward grain and spike photosynthesis might be responsible for sustain grain
growth in this condition.
another http://www.sciencedirect.com/science/article/pii/S0167880905002793
Current-year defoliation increased both quality and production of protein and energy compared to non-defoliated plots
We assessed the effects of elevated atmospheric CO2 on ruminant forage quality and nutrient yields during 4 years in semiarid shortgrass steppe where grazing by
domestic livestock is the primary land-use. A defoliation and a nitrogen fertilization treatment were superimposed on CO2 treatments in large open-top chambers.
CO2 effects on forage soluble and fiber (celluloses, lignin) constituents were small, even though mid-growing season yield and end of season production increased.
However, large negative effects of elevated CO2 were evident in crude protein concentrations and digestibility of forages. While the effects were more negative
mid-growing season than autumn, a reduction in already poor quality autumn forage may be more critical to animals. Crude protein concentrations of autumn forage
on the elevated CO2 treatment fell below critical maintenance requirements 3 out of 4 years, compared to 1 of 4 for ambient and control treatments.
Forage digestibility declined 14% mid-season and 10% in autumn with elevated CO2. Negative effects of elevated CO2 on animal performance mediated through forage
quality are likely to be greater than the positive effects of increased quantity, because quality drops to critically low levels that can inhibit utilization.
Further, elevated CO2 shifted the proportional availability of protein and energy to a species of lower overall quality and the species most negatively affected
by drought. Current-year defoliation increased both quality and production of protein and energy compared to non-defoliated plots, but no CO2 by defoliation
treatment interactions were observed. Nitrogen fertilization increased crude protein concentrations and digestibilities, but not in the least nutritious species
that increased with elevated CO2 or in autumn when quality was lowest.
http://www.forages.ncsu.edu/TechnicalBulletins/TallfescueTB_317.pdf
Research findings show that tall fescue pasture
yield and quality can be greatly improved through
proper defoliation practices and that endophyte-free
tall fescue cultivars can be no-till established into
infected pastures. Further, the experiments show that
with judicious planning and management, producers
can effectively use late summer-accumulated tall
fescue from October to March. These results have
applications wherever tall fescue is grown in North
Carolina and in other mid-Atlantic states.
These are for strawberries http://ir.library.oregonstate.edu/xmlui/handle/1957/25728
The number of trusses and flowers on control plants was significantly lower than on early-renovated plants (2 to 5 WAH). Date of renovation had no significant
effect on yield per plant in the summer of 1990 for all 3 cultivars individually. However, compared with the un-renovated control plants, the pooled yields of
'Benton', 'Totem', and 'Redcrest' showed a significant increase for early renovated plants (5 WAH or earlier). Compared with un-renovated plants, renovation
significantly increased berry size in 'Totem', and delayed the date of harvest in 'Totem' and 'Redcrest' but not in 'Benton'.
one more http://www.sciencedirect.com/science/article/pii/S0031942298004440
However, growth of defoliated seedlings was considerably higher than that of nondefoliated ones.
Last one I could go on forever http://www.sciencedirect.com/science/article/pii/S0378429004000541
Analysis of physiological data collected in 1999 suggests that defoliation suppressed vegetative growth, optimized the ratio of AGDM at anthesis to that at final
harvest (0.50.8, peak 0.66) and led to more AGDM post-anthesis for maximal grain production. Defoliation that led to a yield increase also increased the leaf
area ratio and enhanced stomatal conductance and photosynthetic capacity at anthesis.
It is concluded that defoliation of early (April)-sown wheat defoliated at the middle to late tillering stage could let to greater yield and WUE, and would not
result in yield reduction. The value of foliage removed and overall economic and risk analyses are discussed in a further paper.
None of these plants are like pot that can photosynthesis from there fruit or create leaves on the fruit it is like nothing else. Fruit is usually separate from
leaf like apples.
Defoliation is just another pruning technique like topping, suppercroping, lollypoping or listing.
Topping a plant they go into shock and then develop branches faster then if the top was on.
Supercroping you crush the stem stopping food and water to the branch it goes into shock and stops growing until it heals then gains vigor.
Lollypoping defoliates and removes branches leaving large holes in the stem causing shock till the wounds heal and hormones transfer.
Listing shocks the plant forcing it to change the flow of hormones and stops growth until the hormone transfers and leaves reorientates up.
Defoliation removes large leaf forcing growth to the smaller leaves attached to branches making the branches develop much more replacing the leaf mass in three
days while keeping the top and creating more bud sites with closer nodes and denser branching.
Are any of these methods scientifically proven to work on pot all cause some shock I have never seen a side by side or proof
of any kind that these methods work other that peoples opinion but are not questioned much most try it for themselves. The vast majority of people who have
defoliated are happy with the results I bet a much higher % than the other methods which is why dozens of growers have defended the thread always
against people who have never tried it usually only a couple of haters at a time versus many more who have done it and produce increased numbers from previous grows.
The only people who argue are ones who admit to not trying it but believe the solar panel religion blindly even thou the leaves replace themselves in 3 days
I have read much more than most about this and can not find one person who put up numbers or pictures proving this didn't work only a rare post where it didn't
work for them or they did it wrong I have asked them what happened and they never give details
I have tried all the pruning methods over the years with the exception of supercroping to move a branch I don't care for any of the other methods none have been as good or as fast as defoliation a buddy showed me this years ago when I was part of the solar panel religion till I was converted we didn't do it exactly like the
thread but did see results.
I want to investigate this to the fullest Including real side by sides with numbers for a valued test of timing and amounts with controls which will be started soon.
I thank you for reading this and I hope you look at it with an open mind it is a bit to read and much more to write.
Thanks Bud Brewer out.
Here Is a study Compensatory growth responses to defoliation and light availability in two native Mexican woody plant species
http://journals.cambridge.org/action...66467409990514
Defoliation, often caused by herbivory, is a common cause of biomass loss for plants that can affect current and future growth and reproduction. There are three
models that predict contrasting compensatory growth responses of plants to herbivory and resource availability: (1) Growth rate model, (2) Compensatory continuum
hypothesis and (3) Limiting resource model. The predictions of these three models were tested on the tree Brosimum alicastrum and the liana Vitis tiliifolia.
Seedlings were subjected to three levels of experimental defoliation (0%, 50% and 90% leaf removal) along a light resource gradient (1%, 9% and 65% of full sun).
In both species, defoliation significantly increased leaf production rate and relative growth rate of leaf area, but not of biomass.
Net assimilation rate was the strongest driver of biomass growth in both species, but leaf area ratio and specific leaf area were also important in B. alicastrum.
Compensatory responses of leaf area growth in B. alicastrum were significantly greater in higher than lower light availability, consistent with the compensatory
continuum hypothesis predictions, but in contrast to the growth rate model predictions. The limiting resource model offered an explanation for all possible
experimental outcomes by directly considering the effects of environmental differences in resource availability.
One more http://journals.cambridge.org/action...1447970002353X
Effects of Artificial Defoliation (Simulating Pest Damage) on Varieties of Upland Rice
W. E. Taylora1
a1 Njala University College, University of Sierra Leone, P. M. B. Freetown
Abstract
Artificial defoliation was used to simulate grazing by cutting-grass or cane-rat (Thryonomys swinderianus), on three rices with durations of 110115, 130135
and 140145 days respectively, defoliated before, during and soon after tillering by removing leaves to half, two-thirds and the total height of the plants.
All varieties showed marked compensatory growth, resulting in increased tillering and yield, especially when defoliated during tillering, but yield fell when
foliage was removed after tillering, especially with shorter duration rice. Defoliation to half the height of the plant during tillering had the most beneficial
effect, whereas removal of all leaves to soil level after the tillering stage had the most adverse effect.
And another it produces more corn & double the cotton in dry conditions http://journals.cambridge.org/action...14479703001534
EXPERIMENTAL ASSESSMENT OF THE IMPACT OF DEFOLIATION ON GROWTH AND PRODUCTION OF WATER-STRESSED MAIZE AND COTTON PLANTS
Z. YANG a1c1 and D. J. MIDMORE a1
a1 Plant Sciences Group, School of Biological and Environmental Sciences Central Queensland University, Rockhampton Qld 4702, Australia
Article author query
yang z [PubMed][Google Scholar]
midmore d [PubMed][Google Scholar]
Abstract
In this study, different levels of defoliation were imposed on a determinate species (maize) and a relatively indeterminate species (cotton).
The aim was to quantify the effects of defoliation on plant growth and production, under either optimum or water-stressed conditions. Under well-watered conditions,
33% defoliation twice (conducted 28 and 35 days after emergence) resulted in a 16% reduction in grain yield of maize while 67% defoliation once
(conducted 28 days after emergence) had no significant effect on yield. Under water stress, the grain yields of maize plants with 33% (twice) and 67% defoliation
were 13.5% and 25% greater than that of non-defoliated control plants, respectively. For cotton, the reproductive yields (seed and lint) with 33% and 67% defoliation
(conducted 43 days after emergence) were reduced, under well-watered conditions, by 28% and 37% of that of the non-defoliated control, respectively.
Defoliated cotton plants lost less fruiting forms (squares and young bolls) than non-defoliated plants during water stress. Therefore, under water stress the
harvestable product of cotton plants with 67% defoliation was double that of non-defoliated control plants. In non-defoliated cotton plants, a second flush of
flowering after release from water-stress permitted further compensatory fruit set and boll harvest. Defoliated plants did not show such levels of compensation.
Defoliation significantly reduced water use by maize and cotton. The relative yield advantage of defoliated plants under water-stress conditions can be attributed
to defoliation-induced improvement in water status as reflected in measures of photosynthetic rate and stomatal conductance. Under anticipated drought stress,
defoliation could be an important management practice to reduce drought-induced yield decrease, but this needs to be tested under field conditions.
(Accepted August 5 2003)
Just one more with corn http://journals.cambridge.org/action...21859600062043
Defoliation studies in hybrid maize: II. Dry-matter accumulation, LAI, silking and yield components*
R. P. Singha1 and K. P. P. Naira1
a1 Department of Agronomy, G. B. Pant University of Agriculture and Technology, Pantnagar, India
SUMMARY
Data are presented from an experiment made in two crop seasons, to examine the effects of plant density and degree of defoliation at different stages of growth
in maize at Pantnagar, India, on the dry-matter accumulation in different plant parts, leaf area index (LAI), time of silking and grain yield components.
Different patterns of dry-matter accumulation in various plant parts was observed. Silking was delayed by increasing plant density. Defoliation (even partial)
at the 16th fully expanded leaf stage resulted in substantial reduction in LAI and such yield components as number of ears, ear length, ear diameter and
1000-grain weight. On the other hand, partial defoliation done at the 10th fully expanded leaf stage to simulate an erectophile canopy led to yield increases
even under high plant density (90000 plants/ha) in the Kharif (rainy season), mainly through an increase in number of ears, 1000-grain weight and grain to stover
ratio coupled with a reduction in barrenness and percentage of lodging. It is suggested that an increase in the photosynthetic efficiency per unit area of leaf
resulting from the erectophile canopy is the reason for these effects.
(Received December 18 1974)
http://www.actahort.org/books/218/218_10.htm
LEAF YIELD RESPONSE OF ETHIOPIAN MUSTARD (BRASSICA CARINATA A BR) SELECTIONS TO DEFOLIATION REGIMES
Authors: N.A. Mnzava, W.W. Msikita
Abstract:
The influence of leaf harvest frequency (weekly or bi-weekly) and amount of leaf removal (10%, 50% or 75%) on total yield of three local Ethiopian mustard
selections 'CRRS-V', 'CRRS-II' and 'Mulio Giant' were studied during two consecutive winter seasons in the field. The amount of leaves removed at each harvest
rather than harvest frequency significantly affected total yield which was test cultivar-dependent. Yield increased with defoliation rate to an optimum at 27 t
ha-1 for 'Mulio Giant', and 40 t ha-1 in 'CRRS-II' under either a 50% weekly or 75% bi-weekly harvest frequency, while 'CRRS-V' attained 55 t ha-1 under a
50% bi-weekly harvest frequency. More frequent and intense defoliation tended to prolong the vegetative phase in all cultivars. The physiological consequences
of defoliation on earliness to flower and compensatory growth in relation to yield variation in vegetable mustard is discussed.
This showed no loss in grain weight but increased leaf production and photosynthesis http://www.ncbi.nlm.nih.gov/pubmed/19090232?dopt=Abstract
Effects of timing and defoliation intensity on growth, yield and gas exchange rate of wheat grown under well-watered and drought conditions.
Ahmadi A, Joudi M.
Source
Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Tehran, Karaj, Iran.
Abstract
The aim of this research was to determine the effects of timing and intensity of source reduction on grain yield of wheat under well-watered and drought stress
conditions. A field experiment was conducted at the research farm of the Agriculture College, University of Tehran, Karaj, in 2003-2004. Drought stress was
imposed when plants were at the second node stage by withholding watering and plants were re-irrigated when they showed signs of wilting or leaf rolling,
particularly during the morning. Various intensities of leaf defoliation were performed at three growth stages: booting, anthesis and 20 days after anthesis.
Flag leaf gas exchange parameters as well as chlorophyll content measurements were made 20 days after defoliation at each growth stage. Generally leaf removal
appeared to stimulate an increase of net photosynthesis rate (p(n)) and stomatal conductance (g(s)) of the remaining flag leaf. With leaf removal, stability of
the flag leaf chlorophyll content tended to increase. Neither grain yield, nor protein content were affected by defoliation. Interestingly, even removal of all
leaves at anthesis stage did not reduce grain yield and grain protein significantly. Increased remobilization of stored photoassimilate, decreased maintenance
respiration by source reduction and therefore enhanced photoassimilate partitioning toward grain and spike photosynthesis might be responsible for sustain grain
growth in this condition.
another http://www.sciencedirect.com/science/article/pii/S0167880905002793
Current-year defoliation increased both quality and production of protein and energy compared to non-defoliated plots
We assessed the effects of elevated atmospheric CO2 on ruminant forage quality and nutrient yields during 4 years in semiarid shortgrass steppe where grazing by
domestic livestock is the primary land-use. A defoliation and a nitrogen fertilization treatment were superimposed on CO2 treatments in large open-top chambers.
CO2 effects on forage soluble and fiber (celluloses, lignin) constituents were small, even though mid-growing season yield and end of season production increased.
However, large negative effects of elevated CO2 were evident in crude protein concentrations and digestibility of forages. While the effects were more negative
mid-growing season than autumn, a reduction in already poor quality autumn forage may be more critical to animals. Crude protein concentrations of autumn forage
on the elevated CO2 treatment fell below critical maintenance requirements 3 out of 4 years, compared to 1 of 4 for ambient and control treatments.
Forage digestibility declined 14% mid-season and 10% in autumn with elevated CO2. Negative effects of elevated CO2 on animal performance mediated through forage
quality are likely to be greater than the positive effects of increased quantity, because quality drops to critically low levels that can inhibit utilization.
Further, elevated CO2 shifted the proportional availability of protein and energy to a species of lower overall quality and the species most negatively affected
by drought. Current-year defoliation increased both quality and production of protein and energy compared to non-defoliated plots, but no CO2 by defoliation
treatment interactions were observed. Nitrogen fertilization increased crude protein concentrations and digestibilities, but not in the least nutritious species
that increased with elevated CO2 or in autumn when quality was lowest.
http://www.forages.ncsu.edu/TechnicalBulletins/TallfescueTB_317.pdf
Research findings show that tall fescue pasture
yield and quality can be greatly improved through
proper defoliation practices and that endophyte-free
tall fescue cultivars can be no-till established into
infected pastures. Further, the experiments show that
with judicious planning and management, producers
can effectively use late summer-accumulated tall
fescue from October to March. These results have
applications wherever tall fescue is grown in North
Carolina and in other mid-Atlantic states.
These are for strawberries http://ir.library.oregonstate.edu/xmlui/handle/1957/25728
The number of trusses and flowers on control plants was significantly lower than on early-renovated plants (2 to 5 WAH). Date of renovation had no significant
effect on yield per plant in the summer of 1990 for all 3 cultivars individually. However, compared with the un-renovated control plants, the pooled yields of
'Benton', 'Totem', and 'Redcrest' showed a significant increase for early renovated plants (5 WAH or earlier). Compared with un-renovated plants, renovation
significantly increased berry size in 'Totem', and delayed the date of harvest in 'Totem' and 'Redcrest' but not in 'Benton'.
one more http://www.sciencedirect.com/science/article/pii/S0031942298004440
However, growth of defoliated seedlings was considerably higher than that of nondefoliated ones.
Last one I could go on forever http://www.sciencedirect.com/science/article/pii/S0378429004000541
Analysis of physiological data collected in 1999 suggests that defoliation suppressed vegetative growth, optimized the ratio of AGDM at anthesis to that at final
harvest (0.50.8, peak 0.66) and led to more AGDM post-anthesis for maximal grain production. Defoliation that led to a yield increase also increased the leaf
area ratio and enhanced stomatal conductance and photosynthetic capacity at anthesis.
It is concluded that defoliation of early (April)-sown wheat defoliated at the middle to late tillering stage could let to greater yield and WUE, and would not
result in yield reduction. The value of foliage removed and overall economic and risk analyses are discussed in a further paper.
None of these plants are like pot that can photosynthesis from there fruit or create leaves on the fruit it is like nothing else. Fruit is usually separate from
leaf like apples.
Defoliation is just another pruning technique like topping, suppercroping, lollypoping or listing.
Topping a plant they go into shock and then develop branches faster then if the top was on.
Supercroping you crush the stem stopping food and water to the branch it goes into shock and stops growing until it heals then gains vigor.
Lollypoping defoliates and removes branches leaving large holes in the stem causing shock till the wounds heal and hormones transfer.
Listing shocks the plant forcing it to change the flow of hormones and stops growth until the hormone transfers and leaves reorientates up.
Defoliation removes large leaf forcing growth to the smaller leaves attached to branches making the branches develop much more replacing the leaf mass in three
days while keeping the top and creating more bud sites with closer nodes and denser branching.
Are any of these methods scientifically proven to work on pot all cause some shock I have never seen a side by side or proof
of any kind that these methods work other that peoples opinion but are not questioned much most try it for themselves. The vast majority of people who have
defoliated are happy with the results I bet a much higher % than the other methods which is why dozens of growers have defended the thread always
against people who have never tried it usually only a couple of haters at a time versus many more who have done it and produce increased numbers from previous grows.
The only people who argue are ones who admit to not trying it but believe the solar panel religion blindly even thou the leaves replace themselves in 3 days
I have read much more than most about this and can not find one person who put up numbers or pictures proving this didn't work only a rare post where it didn't
work for them or they did it wrong I have asked them what happened and they never give details
I have tried all the pruning methods over the years with the exception of supercroping to move a branch I don't care for any of the other methods none have been as good or as fast as defoliation a buddy showed me this years ago when I was part of the solar panel religion till I was converted we didn't do it exactly like the
thread but did see results.
I want to investigate this to the fullest Including real side by sides with numbers for a valued test of timing and amounts with controls which will be started soon.
I thank you for reading this and I hope you look at it with an open mind it is a bit to read and much more to write.
Thanks Bud Brewer out.
Bud Brewer
Well-Known Member
I made a post a couple of hours ago with a bunch of studies in it but when I posted from advanced it said I needed mod approval is the normal?
giantsfan24
Well-Known Member
I defoliated my plants last night. I did it in my last grow as well. I got over 10oz on just 3 plants a little over 14" tall in a 2' x 3' x 3' space in my last grow and this grow might just turn out better. It's necessary in my space and environment as it increases airflow limiting the potential for bud mold or PM, gets light further down the plant increasing the size of underbuds as well as making harvesting much easier and quicker. My humidity runs a little high and I have to possibility to run into mold issues.
I've read it's best to do this some in veg then around day 21 of flower, I'm currently at day 17 of flower, then again around day 40. I'm in my 3rd grow now and from my first to my second grow, I doubled my yield.
I'll say this, your environment, temps, light, growing medium, nutes...it's all got to be dialed in for it to work. I'm fortunate to have a near perfect environment so it works just fine for me. Most that have issues also have other issues not related to defoliation that make it impractical to accomplish.
Defoliation has been around for centuries and different plants respond differently to it. I've had positive results in my limited experience.
Namaste
I've read it's best to do this some in veg then around day 21 of flower, I'm currently at day 17 of flower, then again around day 40. I'm in my 3rd grow now and from my first to my second grow, I doubled my yield.
I'll say this, your environment, temps, light, growing medium, nutes...it's all got to be dialed in for it to work. I'm fortunate to have a near perfect environment so it works just fine for me. Most that have issues also have other issues not related to defoliation that make it impractical to accomplish.
Defoliation has been around for centuries and different plants respond differently to it. I've had positive results in my limited experience.
Namaste
Sir.Ganga
New Member
There is validity in all these techniques...The point I am trying to make myself is, yes pulling all the leaves off randomly is a type of defoilation, but not the right technique. Same goes for all the different types of manupilation, topping all the growing shoots does not have the same affect as effectively topping specific tops.
This is where you see the difference in growers, some take the time and do the research and actually learn and make breakthroughs bettering their knowledge base and grow techniques. The other type just wants good cheap smoke or are in it for the money and are not willing to try anything in case they fuck up and loose all that gravy.
In either case...who cares about your reasons for growing but if you have no knowledge pertaining to the topic, do your own research or shut up...some people want this info because Change and advancement is the way to "grow" your knowledge base
If you can't read your plants then you should not be trying ANY techniques
Baby Steps....
Slab
Well-Known Member
Too bad some were not able follow the path of professional cannabis growers & breeders and use those cutting edge techniques that they have honed in a labratory and tested on thousands of plants.
I grow hydrids, and I know damn well what an Overubundance of leaf looks like. not pruning is not an option. so I come to this discussion with limitied predjudice.
the theory of growth hormone response to artificial defoliation is not proven, Brewers research papers describe mixed results.
what I did find interesting was A.D. used in drought situations.
did have me thinking available CO2 to leaf ratio would be a study of interest.
I don't see any of one gettin above average yeilds with the technique.
I grow hydrids, and I know damn well what an Overubundance of leaf looks like. not pruning is not an option. so I come to this discussion with limitied predjudice.
the theory of growth hormone response to artificial defoliation is not proven, Brewers research papers describe mixed results.
what I did find interesting was A.D. used in drought situations.
did have me thinking available CO2 to leaf ratio would be a study of interest.
I don't see any of one gettin above average yeilds with the technique.
giantsfan24
Well-Known Member
Now that it's become legal in a couple of states I think we'll begin to see real research being done that will explode cultivation to new heights. That's my sincere hope at any rate.
Namaste
giantsfan24
Well-Known Member
Slab
Well-Known Member
Indeed, thanks for bringing an air of dignity to the discussion.I hope so..that would be nice wouldn't it?
Namaste
giantsfan24
Well-Known Member
keebo3000
Well-Known Member
found another intersting tid bit... kinda rehashing info but alot of good footnotes
http://forum.grasscity.com/plant-training/668315-defoliating-higher-yields-2.html
http://forum.grasscity.com/plant-training/668315-defoliating-higher-yields-2.html
Trousers
Well-Known Member
This is still going on?
You guys are not even arguing about the same thing. This is worse than the flushing debate.
You like your style? Great!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!111111111 111111111111111
You think your style is best? Great!!!!!!!!!!!!!!!!!!!!!!!!!!!!!111111111111111
Why do people that think their style is the best think that their style is best for some one else's set up?
How do you know your style would work in my set up, with my nutes and my varieties?
Guess what bitches?
My Kung Fu style is better than yours.
[video=youtube;GWhQxQOe5Ms]http://www.youtube.com/watch?v=GWhQxQOe5Ms[/video]
You guys are not even arguing about the same thing. This is worse than the flushing debate.
You like your style? Great!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!111111111 111111111111111
You think your style is best? Great!!!!!!!!!!!!!!!!!!!!!!!!!!!!!111111111111111
Why do people that think their style is the best think that their style is best for some one else's set up?
How do you know your style would work in my set up, with my nutes and my varieties?
Guess what bitches?
My Kung Fu style is better than yours.
[video=youtube;GWhQxQOe5Ms]http://www.youtube.com/watch?v=GWhQxQOe5Ms[/video]
crazyhazey
Well-Known Member
i mean train them so they are in the light, why would you put it in the shadows?