From experience... A plant in veg can be polinated, and produce a seed. It happened on one of my first grows. It was a mother room, just to supply clones for outdoors. i missed one male plant and it let out a lot of polen from its many preflowers. The preflowers on at least one of the females (it's been years) produced seed.
A male in veg does release some polen from its preflowers. Just like a female produces preflowers, which are calyx, just not in the clusters that make a tight bud, or a cluster of pollen sacks releasing a lot of pollen.
Very true. I do exactly the same thing for small amounts of seeds for breeding, use clones with a good amount of pre flowers. The seeds will also develop under 18/6 veg lighting as I found out the first time. Left 1/2 the clones outside and brought the other 1/2 in. Two experiments in one, to see if you could pollinate pre flowers and if seeds would develop under 18/6 lighting. Both were a big yes.
The clones are from a strain I've been running for 3 years or so. I let my kid do the seeds for the males since he's 4 for 4 getting males from seeds.
Can't say much about male pre flowers. Once they start to show male growth habits they are moved outside to flower. Females are killed. Clones are moved outside for a few days when the males start dropping pollen, then brought back inside.
I can work in 2 seed crops/year. One in early Spring and one in late summer. Will be starting seeds for the F3 crop in a week or so.
@HH Trust me, except for a few posters who you can easily pick out, there is
WAY more theory than experience being posted.
Wet