if there was no gnats,my sticks grow roots,sometimes too many...inside of newspaper moist, perlite, moss, you name it, but soon those evil creatures find them... they become food.
what has helped me a bit was to put the semi eaten by gnats in the same pot that has new planted, for some reason, gnats continue working on the already dead ones, and leave the new alone, given it time to get strong. it seems the rooting is 100%dependent of the hungry gnats. not fair!