Lilacs can be divided, but make sure the division has developed enough root mass, or the transplant will not work... I usually will take a 4 to 5 year old plant with enough suckers to make you sick, and dig it up in fall, after the plant has defoliated. I always have great success with them this way, and I always dust the wound with sulfer or rooting fungicide.

I have read that willow water can be used instead of rootone.The aformentioned directions were to cut some young willow leaves and shoots anf cut them up-bring to a boil and use the liquid.I would not boil it.I would soak.Very little liquid.Soak for 24 hours or more.Try both ways-Use a batch for control-with Rootone.Compare results.Do all three.I will try it too.I usually go the rootone route-but this would be cheaper and safer!!!

I watched Dan Hinkley of Heronswood make willow water on a television program some time back, and he cut branches from willow (any willow, not just weeping) - some were as large as a couple of inches in diameter, and a few inches long (short enough they would easily fit into a large pot). He put them in an old kettle (which looked to be at least a 12 qt stock pot, possibly larger), covered with water, and simmered them on the stove overnight, so about 12 hours. Then cooled, drained off the remaining liquid, and put that into a clean lidded gallon container for storage.

The stems he was planning to root were left in a jar of willow water overnight, then inserted into the rooting medium and kept moist.