In article ,
Jeff Layman wrote:

Get a sharp knife and scrape a small piece of bark off about 15 cm above
the soil (or above the graft point if you can see it), If you can see
green underneath the bark, the tree is alive. If, however, it is cream
or brownish, it is almost certainly dead.

You can do this with almost all woody shrubs and trees for a quick check
(but not in a garden centre before you've bought it!).

Most, not almost all. Clematis is an exception, for example. It works
for all the Rosaceae (including apples and plums), as far as I know.


Regards,
Nick Maclaren.