Some trees like willows and poplar can be cut and a cutting can be stuck in the ground and the cutting will grow.
Other trees might need just sticking a cutting into a glass of water to get it to make roots.
root hormones or root stimulators also help to jump-start the process:
Bruce said, " I never knew adding a little honey to boiling water and soaking cuttings in it will help rooting by killing bacteria but the willow water actually has hormones or something that spurs new growth faster. the google searching turned up 7 or 8 different things to help with rooting cuttings besides the little bottle of white hormone powder I';m so accustomed to.
these I found are
spitting on clipping,
apple cider vinegar , 3 tsp/to 1 gal water
ground cinnamon powder
honey, 1 tbsp to 2 cups boiling water
aspirin 1 aspirin dissolved in gallon warm water
willow tea or willow water
aloe vera, pureed aloe gel in blender with bit of water
https://permies.com/t/165823/Root-Hormone-Trees
I hope you will let us know how the mulberry turned out.