I put a ScrOG net and now I am wondering if I should delete everything under the net or leave also the smaller leaves and stems for the flowering. You can see in my diary how the plants are. I'm afraid that leaving also smaller stems under the net would decrease my harvest
You can remove the small stems and the useless leaves under the scrog net. In scrog you want to have a flat cannopy on the whole surface of the box so everything that can't see the ligh will be a burden for the plant during the flowering and you will end with popcorn nugs.
From my recent ScrOG experience where I only did some minor defoliation under the canopy - I ended up with a lot of small/larf bud growth near the end (below the canopy) and small buds at the top. Though the yield was high, the 'work/effort' involved in maintaining all that growth and trimming etc. was really not worth it. My light never penetrated the top canopy and so next time I would definitely be trimming away all branches under the canopy (lollipop) to avoid loss of energy to what would not add value to my yield. I really think it's a matter of light penetration. My canopy was over a foot high and dense (you can check my recent harvested diaries) to see and compare. I don't have a lot of experience but just sharing my observations and thoughts. Good luck.
Why is it a burden? Why is the assumption that cannabis plants put tons of energy into growing small buds? They don't.. They treat small under canopy like they treat leaves that don't get light. You may have a low node during that seeks out and grow up but there is a crazy assumption in thinking the plant uses energy on lower foliage or buds. It doesn't it uses it's available energy to produce buds effectively the key to big fat harvests is intense full spectrum light. Even in full sunlight situations you will always get a top heavy canopy situation. The plant is biologically programmed to make buds and too make buds where it can get the most sun light.
Yes, remove branches and stuff that doesn't make it above the netting, but try not to do it all in one go lest your plant gets stressed out, space it out a bit and keep a watchful eye on her.