I understand it is possible to use colloidal silver (CS) or silver thiosulfate solution (STS) only on parts of a plant and still use the rest of flower if you make sure you don’t contaminate it with the spray.
I’d be interested to know how you guard the rest of the plant while spraying. Any techniques that work well for you?
(Yes, I’d just grow an extra plant and toss it if I had the space, but I don’t. Still would like to collect a bit of pollen one day.)
Plastic bag and elastic bands. Cut a hole for the branch, put the bag over the plant, get the branch through the hole in the bag, rubber band the hole to the branch, then spray.
Take clone and use that otherwise you cant control the pollen flow and you wont have buds to smoke -just lots of seeds. Ive done it and I would of preferred to cs one plant and use it to pollinate another from the same strain. Still a S1.
I want to get autoflower pollen, so cloning is not really an option I guess.
Although … pollen is ready earlier than bud is, so I might get away with an auto clone dropping pollen before it dies maybe? Does anyone know?
Iam about to clone a auto this summer and do this exact same thing. But its a 15 week auto. It should have enough time to root before I start to CS it.
Cool. see my edit, I was just wondering if that might work.
If you dont have a 10 week plus growing auto I wouldn’t try to clone. Cs one auto and use it with the others man. What I did is sprayed on the smallest bottom substems with 120ppm cs. And did that for one week once a day. And it worked. Picked it too early only a couple of seeds popped…it was sad.
The one I have in mind is a 13 weeks auto. 
Just take the clone asap and get it rooted fast AF. As it starts to preflower, spray her. It it doesn’t turn into a male it really was a true female. Which is sad to not breed in itself. If cs can’t turn it male then nothing can!
In my one and only experience making auto fem seeds with CS I noticed that I only collected pollen from the top cola. It would be easy to shield all but the top cola when spraying.
In fact if I was to do it again I would only spray the top cola.
But I would urge you as others have urged me not to smoke from the same plant you spray.
Would it be less of a problem if I’d use it for tincture?
Hashtrees right. Don’t use anything but the seeds.
I thought about using it for topicals, but decided against it. It just wasn’t not worth it after seeing photos of silver poisoning for myself.
just a shield when spraying, chunk of plastic, lid off something, cutting mat, anything to prevent the rest of the plant from being hit… Thats with cs though
I picture something like those cones that dogs have to wear over their heads sometimes as being good.
I’d go with CS. If I understand it correctly, the benefit of STS is less work (spray like three times?), but has to be handled more carefully.
STS is easier to make yourself and be sure of concentration
if you’re that worried about protecting surrounding branches, paint it on with a q-tip or paintbrush or something
If you’re just looking to reverse parts of a plant use an eye dropper to apply the STS / CS to individual nodes. Just a drop per node you want reversed.
To follow up on this:
In the end I used LST and some plastic wrap and tape to separate one branch. I took out the plant and sprayed it in the bath tub every day, spraying away from the plant. I got male parts after two weeks and stopped spraying after 18 days.
I can’t promise there are zero silver particles anywhere else on the plant but I’ll make a tincture from the buds anyway so I’d say everything’s fine.
Thanks a lot to everyone who gave feedback & help!
I’m spraying and auto clone right now. It’s funny because it doesnt seem to be progressing into flowering at all… the mother is part way through