a year ago we purchased a home that the previous owners had cut down a huge Willow tree. A year later, the stump has produced three individual 'trees' coming out from the side of the stump. Now it is very bushy and actually looks great! We want to know if there is anything we should be doing to help it along and what can we expect to happen if we leave the three offshoots on the stump? Will this grow into a big tree again?