"M&K" wrote in message
news:jpPMc.183709$XM6.136043@attbi_s53...
We have a fairly new tree (around 4 years old) in the front yard. It grew
pretty fast and was approaching the 20-ft level. A few nights ago, a gust
of
wind snapped off the top six feet of the tree. The rest of the tree looks
fine, but still needs pruning of the lower branches. A nursery told me to
point a branch near the break to vertical so it would become the central
leader after applying a thin coating of prune sealer to the break. I have
a
bungee cord holding the new leader in place pointing straight up and have
applied the sealer.

1. How long do I need to keep this branch tied up?

Until it stays up on its own. I would guess six months at least.

2. Can / Should I still prune the lower branches this winter? They are
really obnoxious and would they hinder the healing up top?

You can still prune as you would normally.

You didn't mention what type of tree it was. Some fast growing trees often
have problems like the ones you mentioned because their wood is very soft.
In the future, you might consider either an Ash or an Elm tree. Some
varieties of both grow fast, yet are quite strong.