Jane Peppler wrote:

I'm not having any luck finding either of these plants - celtis
occidentalis aka hackberry or sugarberry, or red osier dogwood. Does
anybody know a source of either? Or does anybody have any seedlings or
suckers which I could come pry out of the ground?

If you can't locate any wild Sugarberry (Celtis laevigata) seedlings,
you can buy them from the N.C. Division of Forest Resources catalog -
http://www.dfr.state.nc.us/publications/seed2002_03.pdf
($22 for 100 seedlings). Hackberry (C. occidentalis) is very rare here,
at the edge of its range, though it can be difficult to tell from
Sugarberry.

I don't know much about Cornus sericea, though I wouldn't expect it to
do well this far south.

Will Cook
http://www.duke.edu/~cwcook/plants4birds.html