Help topping for height control and using top for MOTHER ?

I would like to take a cutting of the top of my plant. Reason being I want to drop the height of all my plants and use the tops to be my new mother. I would like to flower the original mothers. My plants are almost three months old and almost three feet tall. This is a sketchy step for me because I have to make sure the new mothers dont die. How easy would the top of the plants main stalk "root" ???
I have had these plants on a drip system in rockwool the whole time. Runing one CFL and on T5 set up. Please help I am needing to move forth on this. THANKS
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The only feedback I can give you, since nobody else is answering ...I personally haven't done this, but my buddy has done what you're doing and has had some difficulty getting those tops to root.

No, you can use the top as a clone and it should root just as easily as any other clone. Just make sure your clones are well and living before you flower your other ones if you are worrying.

Take the cutting just above a node and where you chop her(45 degree) the 2 branches underneath will become your new main colas.

ontarigrow said it all, i just wanted to add that 3ft seems a bit tall for a plant still in veg under CFLs... I'd flower earlier next time

it works i have done it

here man, check my thread about it.- https://www.rollitup.org/general-marijuana-growing/205013-how-top-your-plants-then.html