Very observant, yes, this tree has had some signs of Bacterial Canker
for a long while which is why I was hoping to see the damage to the
other side of the trunk. The gummosis exudes outward through small
slits in the bark. I would have passed along this link below earlier but
the photos did not correspond well to the damage seen on the tree but
now the link will provide a better look at what it is going on in the wood
underneath the bark. Blossom Blight to me is something altogether
different but we can see visual proof how the blast has caused the
limbs to become blighted.
Cherry Bacterial Canker
As a notation: The fumigants listed are not warranted for established
trees with the Bacterial Canker disease. Methyl bromide can come
in handy for non infectious bud failure also known as Crazy Top in
Almonds and Cherries and as a pre-plant fumigant for known Armillaria
root rot and nematodes that exist in the soil but this tree does not show
signs of having them yet. The fumigants are used for seedlings grown in
the ground prior to them being grafted. We have systemic fungicides that
will provide better protection along with cultural suppressing of the disease
but we have to remind ourselves there is no cure for the Bacterial Canker.
We just make amends for us to better live with the disease and try to
cut down on the affects this disease has on the tree. Treated early enough
this tree will probably not die due to this disease but if borers come in or
we get Eutypa dieback or worse yet Cytopsora Canker, then the end will
be near for us. It is the secondary invader that can and usually does hurt
us more than the primary disease does.
A second note: If it were my tree I'd use a systemic fungicide at some
point in time but I've seen enough posts in other threads to know that how
we do things here from the production and home gardener end is looked
down upon in other areas that choose to risk losing someone else's tree
rather than offer a meaningful means to try to take care of it. In the case
of the recommended controls for Ontario in one of the previous links, the
use of topically, dormant and popcorn stage applied Copper sulfate sprays
will probably be best for this tree grown in that home area.