In his book "marijuana botany" Robert Connell Clarke states that:
Leafing is one of the most misunderstood techniques of drug cannabis cultivation.
He states that there are 3 common beliefs:
1.) large shade leaves draw energy from the flowering plant and by removing the large fan leaves
surplus energy will be available and larger floral clusters will be formed
2.) Some feel that the inhibitors of flowering , synthesized in the fan leaves during the long non-inductive days of summer, may be stored in the older leaves that were formed during the non-inductive photoperiod. Possibly, if these inhibitor-laden leaves are removed, the plant will proceed to flower more quickly when the shorter days of fall trigger flowering
3.) Large fan leaves shade the inner portions of the plant, and small, atrophied, interior floral clusters may begin to develop if they receive more light.
Few, if any, of the theories behind leafing have any validity. 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.They do create shade, but at the same time they are collecting valuable solar energy and producing foods that will be used during the floral development of the plant. Premature removal of the fan leaves may cause stunting because the potential for photosynthesis is reduced.
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)
He also states that removing large amounts of fan leaves will also interfere with the metabolic balance of the plant. Leaf removal may also cause SEX REVERSAL resulting from a metabolic imbalance.
He goes on to say that cannabis grows largest when provided with plentiful nutrients, sunlight, and water, and left alone to grow and mature naturally. It must be remembered that any alteration of the natural life cycle of cannabis will affect productivity.
This book has served me very well in my 12+ years of growing--I would have to side with RC on this one--those sunleaves are there for a reason--they dont grow just for show--leave them on there and let that plant grow naturally
Good Luck
Thunderbunny