question one:
can I take a weeping willow branch and plonk it in the ground so it grows into a tree, same as the other willows supposedly do? and if so, any particular branch - young, older, fatter, straighter?

question two:
I found a sapling which I like the look of (running wild on the riverbank, but the council sprays so it could die whether I try and take it or not) but its growing from an exposed piece of root from mumma tree - is there any way to harvest this sapling?

question two part b:
those suckers which grow off (spring out of the base or main trunk of) the main tree - how does one harvest those to replant into a stand-alone tree?

 

and wilz ya there.. mix up some willow water to aid its transition

stand the sapling/cutting in water for a week, don't let the water dry out, dip roots in rooting powder, plant in a large pot with good quality compost, after it has 'taken' replant into garden