Yes they can. I'm pretty sure, depending on the size of the new growth, you should be able to cut them and stick them directly in the ground and they will root. I know for sure you can cut very small limbs from a weeping willow, stick them directly in the ground and they will grow. Juist make sure the soil stays quite moist till frost. Good luck!! Have fun, I love growing plants this way!! It's sooooo rewarding!!