rockm

For what it's worth, the lot isn't "unowned." It's owned by someone since it's being bulldozed and developed. That someone might hold the key to unlocking your problem.

If you can find the owner and tell him you'd like one or two (don't be greedy or you will probably raise the owner's interest in the trees) of the junipers for your yard. Ask him/her if the plants could be taken away when the site is levelled and find out when the dozers are due. Usually site owners will let you cart away stuff they don't want, provided you stay out of the way of the machinery.

The day the work is being done, make sure you are there. Let the operators know you have owners' permission to get a couple of the trees. You might even ask if they'd push one or two of them up for you (obviously taking care not to destroy them and with an aim to getting alot of rootball). This approach could net you a juniper with alot of roots with little effort.

Once out of the ground, placement in a good draining bonsai mix in a growing container large enough to contain the rootball (which may or may not have to be reduced--depending on top reduction and sheer volume).

Winter shelter from the wind is a must. Protection of the rootball from freezing this winter would dramatically increase chances of survival too.