Announcement

**furrysparkle** · 08-28-2018, 09:51 AM

The stretch is kinda set I’ve never read or seen defoliating to slow or stunt a stretch, the main reason for this is airflow the more airflow around your buds the more they stretch out to grab pollen, thus bigger buds

**NAKEDGARDENER** · 08-28-2018, 09:58 AM

You’re not gonna wanna read this as it’s so long and you will disagree with most of it but I paste it here for your amusement.

THEORIES WHY TO TRIM FAN LEAVES
Increase Lower Bud Development
The fan leaves shade lower buds and that these buds do not develop to there full potential because of a reduction in lighting intensity due to shading from upper fan leaves.

To conserve energy for upper bud development
Trimming fan leaves and lower, shaded branches focuses the plants development on main top buds (Che Bleu, 03.13.2002). A plant wastes precious energy several ways. A tall plant needs to use energy to build extra stem, and then use extra energy to move water up higher, this is why I believe "scrog" methods are productive. An untrimmed bushy plant causes the plant to expend energy to build elaborate branches and leaves, and then has to use excess energy to supply all these structures. Careful trimming to remove unnecessary branches (which wont produce nice buds) and unproductive suckers will leave more energy for a larger yield. Suckers do exactly as their name suggests, they suck needless energy from the plant which can be put to better use, towards yield (Leaf, 03.13.2002).

Reduce the Stretch
If fan leaves are trimmed during the early flowering stage, the stretch is reduced (Che Bleu, 03.13.2002). Reducing the stretch might be advantageous in certain cultivation conditions.

Speeding Up The Flushing Process
Remove some of the fan leaves 14 days before harvest. It helps speed up the flushing process and or makes flushing unnecessary (Homemadepot, 03.13.2002).

Reduce The Chance of Mould
Removal of dead fan leaves is necessary to reduce the risk of mould. Failing to "clear the airway" can lead to development of mould in the "crowded" areas of the plant (Jeast, 03.13.2002).

Scrog growers may also reduce the chance of mould by removing fan leaves due to reduce the level of transpiration. This is because many scrog grows are in a confined space where humidity is a serious problem (DoctorDangerous, 09.04.2002). However with better ventilation it may be necessary to avoid the mould problem (Nietzsche, 09.04.2002).

Increase root development on Clones
Fan leaves on clones should have their blades cut in half, to make the clone grow slowly while a root system develops (Weezil, 03.12.2002).

HOW DO FAN LEAVES FUNCTION
The large fan leaves have a definite function in the growth and development of cannabis. Large leaves serve as photosynthetic factories for the production of sugars and other necessary growth substances. Most cannabis plants begin to lose their larger leaves when they enter the flowering stage and this trend continues on until senescence (death of the plant).

Fan leaves account for the greatest area for the reception of photons on a plant, thus they account for the majority of photosynthesis which occurs within a plant. Cells in the plant's leaves, called chloroplasts, contain a green pigment called chlorophyll which interacts with sunlight to split the water in the plant into its basic components. Leaves only absorb about 15% of the solar energy that hits them, the other 85% passes through-- but they reflect all the green light, which means it looks darker below the leaf to a human than it does to the plant because our eyes are most sensitive to the green spectrum (Shipperke, 03.15.2002).

Photosynthesis occurs in all green parts of plants. The process has two stages, the light reactions and the Calvin cycle, that convert water and carbon dioxide into sugar and oxygen. These sugars are later used to power all the processes in the plant, including the synthesis of THC and other cannabinoids (Shipperke, 04.02.2002; Ca, 03.13.2002). Fan leaves possess the greatest number of stomata, which are small pores or valves on the underside of the leaf which water vapor and carbon dioxide diffuse during transpiration and photosynthesis (carbon fixation). Carbon dioxide first enters the leaf through the stomata and combines with the stored energy in the chloroplasts through a chemical reaction (the Calvin cycle) to produce a simple sugar. This sugar is unloaded into the tissues and transported through tubes in the leaf to supply the synthesized food to other plant parts such as growing or respiring tissues like young leaves, roots, and flowers of the plant. meristems (UK Tricky Knome, 03.14.2002).

Removal of fan leaves will not only slow growth, but it will also hinder the plants ability to rid itself of toxic gases, and also hinder the regulation of the plants temperature via stomata. Changes in the plants chemical metabolism caused by fan leave removal causes the plant to work overtime to rid toxins with less leaves, as a result the pant may allocate more growth hormones into growing more leaves to make up for what has been lost(Equator, 03.15.2002). Removing large amounts of fan leaves may also interfere with the metabolic balance of the plant. Leaf removal may also cause sex reversal resulting from a metabolic imbalance.

There is a relationship regarding the amount of carbohydrates a leaf produces and CO2 intake relative to outside forces. When you have a situation whereby the leaf is no longer productive for the plant for whatever reason that may be - low light, old age, disease, insect attack etc, the plant will discard it. (Thunderbunny as citied, by Nietzsche, 03.13.2002.

Plants have two different kinds of vessels in their stems to move stuff around, xylem and phloem. Xylem runs from the roots up the stem carrying water and nutrients. Phloem runs both up and down to move sugars hormones, proteins, etc but mostly sugars. Each part of the plant can be either a sugar source or a sugar sink (Shipperke, 03.15.2002). Phloem moves from sources (areas of supply) to sinks (areas of metabolism or storage). Granted that the flowers can produce some photosynthate, but they are no where near as effective as fan leaves (resin glands significantly reduce light to the tissue they are found on). Flowers are sink tissues, leaves are source tissues. Sinks do not produce enough photosynthate, and are importers. Sources give photosynthate to sinks in closest proximity. Upper leaves bring sucrose to shoot apical meristem and young leaves while lower leaves bring goodies to roots (UK Tricky Knome, 03.17.2002). Remove the source and the sink will be affected (Diels Alder, 03.15.2002).

The leaves at the top of a plant tend to supply the top growing shoots. The leaves at the bottom of the plant tend to supply the roots. The middle leaves can go either way as the demand changes. During flowering and fruiting, only the very bottom leaves supply the roots and the rest of the leaves try to get as much energy as possible to the flowers of fruits. For this reason, the more leaves are unshaded and in good light, the more chance the plant has of creating extra storage of energy that will ultimately go into yield (Leaf, 03.13.2002). However Jeast (03.13.02) believes that the rich green leaves emerging from the bud are a sufficient energy source of solar energy for the plant's floral development. Therefore the old fan leaves are once again rendered useless and only drain energy from the developing part of the plant (Jeast, 03.13.02).

Fan leaves store mobile nutrients, these stored nutrients are essential in the later stages of flowering. When flushing a plant the fan leaves will lose their color quickly. This is because the nutrients are being mobilized to the atypical meristem (grow tip, bud site). Draining your fan leaves with a flushing period will increase floral development (Ca, 13.03.2002). Fan leaves therefore serve as a nutrient deficiency buffer zone for the plant (Higstar, 03.13.2002).
Nutrient burn usually causes bottom leaves begin to die however DaGnome (03.15.2002) observed that if you do not remove the leaves then they will absorb damage as premature removal generally results in more leaf loss. However if growing hydroponically under ideal conditions it could be argued that fan leaves serve as a nutrient buffer is a moot point.

WHEN AND WHAT TO TRIM IF AT ALL
To trim or not to trim that is the question. Try everything for yourself. Try it all ways. (The Crazy Composer, 13.03.2002). Simply put there is no universal answer it depends on how your are growing when where and what you trim (Cardboardbill, 03.13.2002)

Genetic Variance
Cannabis phenotypes play a large part. A strain with very few leaves and long internodes will need a lot less trimming - if a trimming technique is even adopted. A strain with a surplus of leaves and short internodes would require more thinning to get the same amount of light to the lower buds (The Crazy Composer, 13.03.2002). Cannabis varieties from high sunshine equatorial areas like thai sativa have thin leaves most likely due to more light than say a indicia plant from afghan regions have wider fan leaves due to less light intensity in their natural environment (Lebman, 03.20.2002).

Remove non productive dead leaf material
Here are some signs to look for when removing foliage. Leaves that have reached their final size and are ageing will stop producing chlorophyll and start changing to a lighter color, often yellowing and showing purple petioles (leaf stems). This is when the leaves' capacity to produce sugars starts to diminish, so they are the ones to take out of the way to allow Sunlight to fall on the younger leaves that are producing at a higher rate. The older leaves, even though larger, are no longer very productive once they are not dark green anymore. By the time they start looking pale or discolored, they are not contributing anything to the plant at all. Obviously, the lower leaves are the oldest and the first to age. Old leaves can be removed at any time they are shading younger ones, but try to never remove a leaf in its expanding stage because it is producing at full power (Leaf, 03.13.2002.

Outdoors, fan leaves serve an additional and very important purpose of protecting the buds from the elements and predators. These leaves often become damaged in the course of doing their duty, and will then wither or break off (Jeast, 03.13.02). However depending on the humidity of the growing climate Leaf (03.13.2002) suggests to trim most leaves that show signs of age, are dull in color, yellowing, and obviously any brown or spotted leaves that have bugs or bug damage to prevent mould.

To Increase Lower Bud Development
Light efficiency decreases with distance. The inverse squared light rule states that illuminance is inversely proportionate to the square of the distance from the light source.
Removing the largest area of photosynthesis that is closest to the light source simply to benefit smaller leaves growing out of the but sites that are further away is not logical when growing indoors"(Smokinrav, 03.15.2002). Cultivating outdoors under the sun, the fan leaves don't create nearly as much shade as they do indoors (~shabang~, 03.13.2002). This is consistent with the inverse squared light rule; the sun is 149,597,890 km away so a few feet has no real effect on intensity. This suggests that a trimming benefit could be achieved outdoors as opposed to indoors however leaves only absorb about 15% of the solar energy that hits them, the other 85% passes through except for green light which is reflected, therefore removal of fan leaves would only provide a 15% increase light transmission outdoors (Shipperke, 03.15.2002).

Jeast (03.12.2002) removes fan leaves that are yellowing or starting to yellow (these are usually on the lower stems) and also mid-stem fan leaves that are shading buds. He always try to retain the upper 2 - 3 sets of fan leaves indoors as he believe they are the ones that are truly "working". The concept of the upper fan leaves doing all the work is consistent with effect of the inverse square rule on lighting intensity indoors and the flow on effect for photosynthesis. In support for trimming HyGradeChronic (03.25.2002) states selective trimming benefits lower floral development, allowing the buds to fill out and tighten up better. However he does mention that humidity must be kept to a minimum as leftover stems from the leaf can develop mould unless kept at optimum humidity. Another flow on effect to leaf trimming mentioned by HydradeChronic is that it takes seven to ten days longer for floral development to finish, but the resulting florescence is at its peak from top to bottom.

An alternative to trimming to increase light to lower floral clusters is to use a light mover on a single plant the results are better thanks to the better penetration of light at different angles. Even simple under lighting and side lighting works well to counter fan leaves by adding extra light where it would not normally get (Vapour, 03/13.2002).

Increase upper bud development
What folks need to focus on is the causes of premature leaf drop as that negatively affects yields. If you've read my posts over the years, I try to pound that issue home whenever given a chance. After a good root development, the most important element in floral production is the retention of healthy leaves (Thunderbunny as citied, by Nietzsche, 03.13.2002).

Green Reaper (03.12.2002) suggests that large leaves actually take more energy to maintain than they produce. In contrast Thunderbunny (as citied, by Nietzsche, 03.13.2002) states that when a leaf no longer serves a productive purpose, the plant will remove the leftover metabolites from the leaf, which causes the old spotty, yellowing, necrotic image and then the leaf drops. Once that leaf is gone, a percentage of what would be available carbohydrates for future plant growth is diminished in direct relationship to the loss. The mobility of plants sugars and nutrients suggests that fully developed fan leaves are sources not sinks. Whether developing fan leaves are a sink or a source however is not as clear. An actively growing leaf may be a sink, using energy from the other parts of the plant to fuel their development (George, 03.20.2002). Older developed leaves and that are sources. However there is no evidence to support that during the plants life cycle the development of fan leaves takes more energy then a fully developed fan leave provides, that is to say sink phase is greater than the source phase (Nietzsche). It would also seem illogical from an evolutionary point of view that a plant would evolve to produce leaves that take more energy to sustain then they produce (~shabang~, 03.13.2002).

Trim fan leaves in the last 14 days to help speed up flushing
It helps speed up the flushing process and or makes flushing unnecessary (Homemadepot, 03.13.2002). However the leaves should naturally yellow, too much green in the leaves translates to too much "green" taste in the leaves in my opinion (Bigislandbud, 03.14.2002).

Reducing the Stretch
If trimming fan leaves reduced the stretch it is likely that this occurred because it takes away from the plant's available energy stores and energy generators (~Shabang~, 03.13.2002). This method of reducing the stretch should only be used if absolutely necessary, other options include chemical treatment may be a more viable option.

HOW TO TRIM IF YOU CHOOSE TO DO SO
If you decide to trim your fan leaves, one should always do it by clipping the petiole about halfway between the base of the fan leaf and the stem/branch. Allow the remainder of the petiole to dry up and fall off on its own. This will help protect the plant from risks of infections. They should never be stripped or broken off at the base of the petiole as that would be expose more chance of infecting the plant. Petiole is the he foot stalk of a leaf (10k, 03.16.2002)

Leaf (03.13.2002) believes that excessive leaf trimming and branch pruning will cause the plant to use extra energy to repair itself. However, trimming must be done from time to time, for the longer a plant is left untrimmed, the more material must be removed at one time, therefore the greater the damage that the plant will need to repair. Do not trim fan leaves during veg either, unless they turn yellow. The first real pruning starts when going into 12/12 (Jeast, 03.13.2002). When trimming and pruning, I try to ensure that I do not cause the plant to 'bleed'. Leaf tries to pinch off shoots and leaves with my fingernails as opposed to leaving a clean cut. One thing to remember is every time you cut into any part of a plant, you are exposing the inside of the plant to fungus and bacteria (Leaf, 03.13.2002).

Tuck instead of trimming
Another method is to tuck your fans leaves under to expose the buds, don't forget that even though they wont be getting as much light they are still photosynthesizing and more importantly exchanging gases storing nutrients, and building sugars which the bud then converts into THC and other cannibinoids (Ca, 13.03.2002)

**D.A.A.S.69** · 08-28-2018, 11:37 AM

PaganRich, what's going on Mate, are you feeling good today ? We just got thru listening to Tulls, Thick as a Brick ,album, some kind of good music !!! It gets you charged up, lol.
I wish i could tell you , but I ain't no plant scientist, But as both you and I know, if you want big ass buds, you got to remove some leaves so them bud sites can get as much light as possible.
If those bud sites are covered by leaves , your buds will be pitiful specimens.

Stay Cool an Mellow ,Cheers.

**DrPhoton** · 08-28-2018, 02:39 PM

Although i believe i a lot of what was said, i have to point out the errors and dissagree with main points about trimming. Clearly he has read a book or two but failed to learn the fundamentals of photobiology and somehow twisted things to support his conclusion.

"A tall plant needs to use energy to build extra stem, and then use extra energy to move water up higher, this is why I believe "scrog" methods are productive. An untrimmed bushy plant causes the plant to expend energy to build elaborate branches and leaves, and then has to use excess energy to supply all these structures. Careful trimming to remove unnecessary branches (which wont produce nice buds) and unproductive suckers will leave more energy for a larger yield. Suckers do exactly as their name suggests, they suck needless energy from the plant which can be put to better use, towards yield."

Water movement in plants is a passive hydrostatic process through transpiration, there is no energy lost or provided in the movement of water. I do agree about careful trimming though.

"Reduce the Stretch
If fan leaves are trimmed during the early flowering stage, the stretch is reduced (Che Bleu, 03.13.2002). Reducing the stretch might be advantageous in certain cultivation conditions. "

Theres no scientific research i could find to support such a conclusion, even his cite fails to be found.

"Speeding Up The Flushing Process
Remove some of the fan leaves 14 days before harvest. It helps speed up the flushing process and or makes flushing unnecessary."

Im not finding any material provided by this person, at all.

"Increase root development on Clones
Fan leaves on clones should have their blades cut in half, to make the clone grow slowly while a root system develops (Weezil, 03.12.2002)."

Removal of fan leaves is about transpirational water loss, not growth suppression. I am begginning to wonder whether his cites are from forum members.

"Leaves only absorb about 15% of the solar energy that hits them, the other 85% passes through-- but they reflect all the green light, which means it looks darker below the leaf to a human than it does to the plant because our eyes are most sensitive to the green spectrum (Shipperke, 03.15.2002). "

Many plants, including cannabis have been shown to absorb around 80% of light, with about 20% transmittance and reflectivity profile. Green light is only slightly more reflective than other wavelengths and its this combined with the human eyes weighted sensitivity in green that is the reason why plants appear green to us. Most plants absorb around 80% of green. Green can actually be absorbed ore than other wavelengths due to the aspect of the seive and detour effect. Which just so happens to work on the principle of increased transmittance. Now i see what it is, hes referring to forum members. Not very helpful.

"The leaves at the top of a plant tend to supply the top growing shoots. The leaves at the bottom of the plant tend to supply the roots. The middle leaves can go either way as the demand changes. During flowering and fruiting, only the very bottom leaves supply the roots and the rest of the leaves try to get as much energy as possible to the flowers of fruits. For this reason, the more leaves are unshaded and in good light, the more chance the plant has of creating extra storage of energy that will ultimately go into yield (Leaf, 03.13.2002). However Jeast (03.13.02) believes that the rich green leaves emerging from the bud are a sufficient energy source of solar energy for the plant's floral development. Therefore the old fan leaves are once again rendered useless and only drain energy from the developing part of the plant (Jeast, 03.13.02)."

He should know better that leaves are sources, not sinks. Once leaves emerge from development they become sources and stay as sources until sensence. Which by that time the plant recognises that the leaf in question is no longer able to manufacture enough energy. So is made redundant and valuable resources recovered from the leaf prior to abscission. He further cites sources that are either not easy to find or are books or people from forums.

"WHEN AND WHAT TO TRIM IF AT ALL
To trim or not to trim that is the question. Try everything for yourself. Try it all ways. (The Crazy Composer, 13.03.2002). Simply put there is no universal answer it depends on how your are growing when where and what you trim (Cardboardbill, 03.13.2002) "

The Crazy composer ? Now imsure hes citing forum members.

"To Increase Lower Bud Development
Light efficiency decreases with distance. The inverse squared light rule states that illuminance is inversely proportionate to the square of the distance from the light source.
Removing the largest area of photosynthesis that is closest to the light source simply to benefit smaller leaves growing out of the but sites that are further away is not logical when growing indoors"(Smokinrav, 03.15.2002). Cultivating outdoors under the sun, the fan leaves don't create nearly as much shade as they do indoors (~shabang~, 03.13.2002). This is consistent with the inverse squared light rule; the sun is 149,597,890 km away so a few feet has no real effect on intensity. This suggests that a trimming benefit could be achieved outdoors as opposed to indoors however leaves only absorb about 15% of the solar energy that hits them, the other 85% passes through except for green light which is reflected, therefore removal of fan leaves would only provide a 15% increase light transmission outdoors (Shipperke, 03.15.2002)."

I would suggest he picks up a book on light physics and read up about point sources and EMF attenuation in free space. Too much assumption in these writings. Again, his conclusion of light characteristics with leaves is incorrect.

"Green Reaper (03.12.2002) suggests that large leaves actually take more energy to maintain than they produce. In contrast Thunderbunny (as citied, by Nietzsche, 03.13.2002) states that when a leaf no longer serves a productive purpose, the plant will remove the leftover metabolites from the leaf, which causes the old spotty, yellowing, necrotic image and then the leaf drops. Once that leaf is gone, a percentage of what would be available carbohydrates for future plant growth is diminished in direct relationship to the loss. The mobility of plants sugars and nutrients suggests that fully developed fan leaves are sources not sinks. Whether developing fan leaves are a sink or a source however is not as clear. An actively growing leaf may be a sink, using energy from the other parts of the plant to fuel their development (George, 03.20.2002). Older developed leaves and that are sources. However there is no evidence to support that during the plants life cycle the development of fan leaves takes more energy then a fully developed fan leave provides, that is to say sink phase is greater than the source phase (Nietzsche). It would also seem illogical from an evolutionary point of view that a plant would evolve to produce leaves that take more energy to sustain then they produce (~shabang~, 03.13.2002). "

The sink to source transition has been clearly imaged through fluorescent doping which displayed wonderfully the loading and unloading of photoassimlates.

This is not intended to insult you NAKEDGARDENER but i would take what is written by this person, with much less than a grain of salt. He has clearly done some research but failed along the way to verify his data and use the right resources to understand the basic principles of plants and photobiology. I mean he references people from forums most of the time. Thats not helpful, just counter productive.

Sorry to detour your thread PaganRich

**DrPhoton** · 08-28-2018, 02:52 PM

Hey D.A.A.S.69

Can you please tell me or even you PaganRich, whether autoflowers appear to exhibit the same types of flowering stretch as photoperiods do. ?

Much appreciated.

**Greengringo** · 08-28-2018, 03:23 PM

That was brilliant!! Dangerdan and on point.

**NAKEDGARDENER** · 08-28-2018, 05:06 PM

Like I said @ dangerdan @ paganrich @ greengringo, I posted that not as something I support or read and believed, I saw the same response to this article where it was originally posted and wanted to show that sometimes what is published isn’t based from someones experience or education but from a need to appear so, whether any of the facts he presents are erroneous, in correct or plain bs, is just another part of the cloudy atmosphere I have discovered since returning to cannabis growing, the people themselves and how it fluctuates on who knows what and best way to do it, I’m no scientist nor any way knowledgeable about cannabis growing, but I have worked with trees and shrubs in some high end garden centers to understand the basics of plant biology and differing species needs, Dangerdan has helped me with lighting questions, and whilst I admit often I still struggle with full understanding, what I have learned has helped me immensely to try and give my plants the right light at the rights stages of growth. Others have helped with with super cropping or scrogging, and even super defoliation, all of these things I knew nothing about on my first grow back in the 80s, I’m sure non of it existed, so forgive me if sometimes I fuck up, it’s not intentional but I am certainly not trying to mis inform or misguide anybody.

**Weed Pharma** · 08-28-2018, 08:03 PM

There are a few things that effect stretching from the day/night temperature difference to the light's color spectrum, etc.
A crowded plant for instance will stretch looking for light- much like a seed which has just popped through the ground.

I've never thought about Schwazzing having any effects on this.
One thing about the technique, which is rarely mentioned- it involves a nutrient regiment which re-introduces (increases) micro nutrients during the 5th week of flower: which is the last defoliation under Schwazzing.
I have used Scwhazzing and many other "yield boosting" defoliation schemes and have found no difference in quality or quantity.

The more I grow- the more I believe in my signature! below

Announcement

Question: Schwazzing and the Stretch

Question: Schwazzing and the Stretch

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment