British Columbia: Can anthracnose cause a dogwood branch to split?

My friend in Qualicum, BC has a beautiful pink dogwood in a seemingly perfect location in her garden but which is exhibiting obvious signs of anthracnose. There are lots of small, dead, interior branches and dry withered leaves studded with black fungal dots. This has been a particularily good year for fungal problems of all sorts, I'm sure.

What is puzzling to me though is that one branch has developed a long, horizontal split, all the while bearing an abundance of lovely pink flowers toward its outer reaches. My first thought was that heavy snow last winter may have weighted the branch down to the point where it split but my friend doesn't think there was enough snow to do that. Another branch is showing signs of developing a similar split.

What I'm wondering is if we're looking at 2 different problems or if anthracnose could somehow cause a branch to split. I've recommended that she try to save the branch by closing the gap and then shortening the length of the branch in the dormant season.

Have any of you run across this problem (or problems) before?

 

That appears to be a type of crack called a "hazard beam" It often occurs right at the central shear plane....that is, the point at which the opposing compression and tension forces meet. All hazard beam cracks should be considered as a high risk of failure. Each piece can act mechanically independently of each other.

If there are no targets under or near the tree, the branch may be fine for many years. It will develop callous wood. If you remove it use the three point cut: Search Dr. Alex Shigo or the ISA for tree pruning info

 

Thank you for the information you have provided . . . 'hazard beam' is a new term and a new concept for me so I have spent some time researching more about the condition and will pass this all on to my friend. I think she's decided to leave the branch until late fall when the sap has stopped running to cut it right off (3-point cut in mind). The anthracnose symptoms seems to affect mainly the lower branches, of which the split branch is one.

Thank you again for taking the time to reply - this is the first question I have posted to UBC Forums and was beginning to think I wouldn't hear hear anything back.