Can I topwork macs with fireblight?

[NY_Terrence]

I know it is a strange time of year to be talking about fireblight, but I need some advice. In 2008, I planted about 16 macintosh trees. The idea was that the future orchard would serve as a hunting spot close to the cabin for my boys as they grew up and my father as he got older. So, eight years later, I have had very few apples. Why? I think the trees were getting little sun and had shoot fireblight the past two seasons. Now what? Well... I cut down trees that were blocking the sun. I have since learned that macs were never a good choice for fireblight or for dropping apples during the hunting season. I have learned to clean my pruners after each tree so I don't spread the blight. Finally, I have had success with bench grafting and topworking the past two years. Now, I'm considering topworking these tree over to a more favorable disease-resistant & late dropping variety - or am I too late? Should I just pull the trees out because of the fireblight and plant new ones? Thanks for your help.

 

[Turkey Creek]

No you are not too late to make something good out of your situation. You will want to cut off the trunks say at 3' height and then bark graft your preferred choices. The established roots will give your grafts great growth, likely leading to ealier fruit production than starting from scratch. Most people would likely leave a nurse branch until the grafts take and push some new growth. You remove the nurse branch at that time. Just make sure you dont have any fireblight cankers on the trunks you leave. Fireblight normally enters trees through blossoms and new growth so the Macintosh trunks should pose no problem.

 

[Rally1148]

No you are not too late to make something good out of your situation. You will want to cut off the trunks say at 3' height and then bark graft your preferred choices. The established roots will give your grafts great growth, likely leading to ealier fruit production than starting from scratch. Most people would likely leave a nurse branch until the grafts take and push some new growth. You remove the nurse branch at that time. Just make sure you dont have any fireblight cankers on the trunks you leave. Fireblight normally enters trees through blossoms and new growth so the Macintosh trunks should pose no problem.

Will that work with a mature standard tree? I've got a few that are about 15 inches across that could be saved if this works.

 

[Turkey Creek]

Will that work with a mature standard tree? I've got a few that are about 15 inches across that could be saved if this works.

Yes in theory. The bad thing though is you have a large exposed wound that would likely not callus over at least for a very long time. You would want to do a bark graft every 2-3" around the perimeter of the trunk. In your case it would be better to cut off limbs higher up in the tree where the diameter isnt as great and bark graft there. I personally have not bark grafted anything over 4" in diameter, maybe somebody on here has and they will relate their experience.

 

[greyphase]

I'm going to try this method on several big trees I have.

My bark grafting skills leave much to be desired, so I'll let some suckers grow out and then cleft graft to them and see what happens o_O.

 

[chickenlittle]

McIntosh is not a bad variety for fireblight, often rated moderately resistant. It is bad for apple scab.

Assuming you are correct that your issue is fireblight, I would still try to save as much of the tree as possible. Why cut it down to a tall stump and force your new varieties to essentially start over? Cut back into mature wood of your limb structure and cleft graft to those. You might be up on a ladder and need a bunch of scion wood but it will get your trees into production much faster.

Be sure to look at ugly stub pruning to know how to handle blight. YouTube videos are good for learning that.

 

[NY_Terrence]

Thank you all for the input. It is so appreciated. I am relieved that I can save the tree and love the idea of trying to save as much of the trees as possible. It would be a shame to lose all the growth from the last 8 years. Definitely going to take a bunch of scions. I have about 45 other apple trees, but they were planted in 2014 and 2015 so not sure how much scion I will be able to pull from them.

 

[Rally1148]

Yes in theory. The bad thing though is you have a large exposed wound that would likely not callus over at least for a very long time. You would want to do a bark graft every 2-3" around the perimeter of the trunk. In your case it would be better to cut off limbs higher up in the tree where the diameter isnt as great and bark graft there. I personally have not bark grafted anything over 4" in diameter, maybe somebody on here has and they will relate their experience.

That was my one reservation about doing it. I have some pictures I'll put up eventually to show why I'd be cutting it down. It's got some fb and is losing some bark in other areas. it's a 50 year old tree though, so it might just be reaching the end of its life.