Best practice for a dead/decaying leader

[Chris_Robinson]

This may seem like a question with an obvious answer to many, but I found my mind arguing with itself trying to consider which option would be best for the health of a tree. Consider a 40 foot medium sized red ash whose top has snapped off 3/4 of the way from the ground to the branch tips and is left alone. The laterals continue to leaf out year after year and the lateral closest to where the top broke off begins to turn upward to assume the terminal role. But after a couple years, the piece between the now highest branch, and where the top broke off, begins to decay. My question is this: What is better for the health of the tree, assuming that there are no targets present that could be damaged if the decaying piece breaks off: leaving the tree as is, or making a reduction cut at the new highest branch? The piece that would be cut off would leave a wound much larger than the tree could ever close. All my instincts and everything I've learned tell me that the reduction cut will be better for the health of the tree. However, my tendency to question everything kicked in and wondered if leaving the tree as is would be a better option. From what I understand, reduction cuts don't compartmentalize as well as cutting a lateral back to a parent stem, so why not just leave the decaying stub in place? If it were cut off, wouldn't the remaining trunk decay faster as the wound remains exposed to the elements? Conversely, if it were left in place, the remaining piece would continue to decay, but it would take longer for the decay to reach the part of the trunk that would be exposed if the reduction cut were made right away. Thoughts?

 

[oceans]

Can you make a nodal cut above the highest branch and see if she sprouts out some new leaders that could be trained over time? What's the diameter of the stem at the point of failure...and, was it an inclusion at that point?

 

[banjo]

If there are no targets involved why not let nature run its course? You could subordinate competing leaders and weight reduce the suspect one but will you be pruning for dollars or tree health? Trees in nature do just fine without us. Is the tree in question a valued component of the landscape, or is it something in the periphery that could be replaced?

 

[evo]

If it were here, and no targets with in lets say 15 years I'd let it be. Perhaps making a nodal cut to reduce the surface area of where the leader broke at. It all depends on where the tree is at on the site.

 

[pinus_rigida]

I think a reduction cut would be appropriate immediately after the top broke out. However if considerable time has gone by, the tree has already responded to the wound. Codit does not do a great job of describing the reaction to this type of wound,(only wall #1 applies?) but surely the tree has put energy into stopping the spread of decay. If more than a growing season has passed I wouldn't make a reduction cut in order to avoid breaching that zone of reaction.

 

[Frax]

I think your wondering about it is worthwhile and there may not be an obvious answer in every case. More and more, I have elected not to cut back to a textbook collar cut in cases where breakage and possible decay might have gone on for some time.