ok most people use the col. silver mix spray that can be found on places like ebay. they recommend spraying the branch twice a day until you see sacks appear, what i would say is spray once a day and if you see signs of damage caused by spray then dilute the spray using distilled water. also spray on a uper branch and not a lower one, this will give you enough pollen. you can not smoke the bud on the plant you sprayed but you can how ever still make hash out of it.
if your looking for about 50 seeds, that may be high, but it may also be doable.
heres what i would recommend, spray your picked branch, if you can keep the plant separate from the others, when you see some thing happening on the sprayed branch it is the start of a reversed male, at this point there is maybe 2 weeks until the reversed flowers start to push pollen, i would put your plant you wish to seed up in with the other sprayed plant, you should cover most of the top of the plant with a bag and use a few lower branches for seed, also if you can try to collect the pollen by using a piece of black construction paper, collecting the reversed pollen is hard as some times you do not get much, now with your chosen plant you want to pollenate,
once you pollenate the branches, you should start seeing with in a few days the hairs on the bud will start to turn amber and they will look different than the other buds,
you also want to pollenate the chosen plant(s) between the 3rd and 4th week of flower, as the seed will take time to mature and you should leave the seeded branches on the plant 2 weeks past your harvest date
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