Perhaps reading this will help. Note that it is Garden Myths website 😉

https://www.gardenmyths.com/transplanting-should-you-reduce-top-growth/

@gardengal48 (PNW Z8/9) It would be nice to see this tested in a real study. My guess is in some cases he is right and the shrub/tree wants energy stored in the stems. But in other cases, the plant drying up and dying all over rapidly might reflect a transpiration issue, in which case reducing the surface area where transpiration takes place might save the plant.

I get the point that you cannot generalize this, and telling the difference between the two cases is probably not something I will do well.

@gardengal48 (PNW Z8/9) Okay, but I did do a brief search in Google Scholar, which gives a much less clear indication that top pruning will not affect survival. I will also say that Dr Scott's article contains no citations, and having interacted with her Facebook group, you quickly realize they are extremely anti-scientific in most of their discussion. God forbid you actually show them scientific evidence. What really matters in that group is that you repeat the words they tell you to speak, like a mindless robot.

These are just two random studies:

https://www.tandfonline.com/doi/full/10.1080/15592324.2019.1621246

https://www.auburn.edu/academic/forestry_wildlife/nurserycoop/PDF%20files/effects%20of%20top-pruning%20on%20survival.pdf

In the first study:

"Repetitive pruning increased absolute root dry weight 43% to 61% and root:shoot ratio 55% to 56% above that of control plants that were not pruned. One year after out-planting, the pruned plants were greater in shoot dry weight and plant height than the control plants. More importantly, control plants exhibited 70% to 80% mortality, but the pruned plants exhibited 100% survival."

Okay, that was for one specific species. And it is about pruning while the plant is growing, not pruning as a rescue method, but it does hint at the idea that reducing the burden of leaves on a transplant may be helpful.

The second study:

"Published studies suggest that top-pruning can increase overall survival of loblolly pine and longleaf pine by 7 and 13 percentage points, respectively. Pruning various hardwood species (mainly after lifting) increased average survival by 5 percentage points. Benefits of top-pruning appear greater when seedlings experience stress after planting and when non-pruned seedlings have low root weight ratios (root dry weight/total seedling dry weight). On some droughty sites, a seedling with a 0.3 root weight ratio might have a 26 percentage point higher chance of survival than a seedling with a 0.2 root weight ratio."

Again, that is for a different genera of plants, but the results do suggest top pruning enhanced survival and they say explicitly that the benefits are greatest when the plants experience stress after planting, which is my case.

We might run a scientific study on my exact plant and do the pruning after the stress of a transplant develops. That study might end up showing I kill the plant more often by top pruning it. But a quick search of Google Scholar would show anyone that my idea is not being pulled out of thin air, and there is a non-zero chance that my idea might improve plant survival.

I am not going to argue with you. You asked and I answered. I have seen plenty of documentation that supports both of those individuals' writings. And to claim Chalker-Scott is anti-science is preposterous!! The woman has a PhD in Plant Physiology!

btw, you cannot perform a scientific study on a single sample. It will not be the slightest bit accurate or representative.

" I will also say that Dr Scott's article contains no citations "

The articles are not intended to be a scientific report but a very basic and understandable presentation for the layman on these issues. If you contact her directly, she can easily provide all the citations you need.

@gardengal48 (PNW Z8/9) I am not arguing or asking you to argue. I am making the point that science has a less clear view of this topic than the two blogs you considered suggest. I am okay with you having your point of view.

I understand that a real study on this topic would need to involve dozens or hundreds of specimens in carefully controlled conditions. I was trying to draw from studies that did this. Clearly, my N=1 proves nothing. I agree with you.

I am not saying Dr Scott is not credentialed. She is very smart and very experienced. But you should spend some time in her FB group and deal with her admins and then you will have a different opinion.

I asked a question there about container soil and was told to use garden soil as my container soil. Garden soil in my container? This is science-based?

When I tried to explain why many plants would die in that container mix, I was told "wrong plant".

When I tried to explain Tapla's gritty mix, I was told "no advertising brand names" like "Turface". When I changed my text to use a generic term "calcined clay" the admin went into a uncontrolled rage that I was forbidden from discussing topics that did not involves native soil.

When I showed them studies that Turface improves the container growth of certain plants, I was told I am disodient.

When I tried to ask a question to Dr Scott, one of the admins hid my replies so no one in the group could see what I was saying. When I proved that to her by using a friend's FB account, she said "well that comment did not matter anyway". Which proves she knew that she had hid the comment!

The truth is that you and Tapla are among the most experienced gardeners around, but neither of you would last more than a few months in that FB group. Because that FB group is not about gardening science, or about science. That group is about ego, at the expense of science.

Agree w/GG. Stems have food in them. If a transplant results in the roots not being able to support all the stems, the tree will manage to withdraw/save some of the food out of the stems that are dying. Later, cut off the dead stems.

My suggestion was to contact her personally directly, not via the Facebook group. Her email address at WSU is available on her website.

LOL!! My personal opinion is that Facebook is a massive waste of time. I do not belong nor do I have any desire to.

@bengz6westmd In both of the peer-reviewed studies that I linked, survival of the transplants improved with top pruning. In all of those hundreds of cases, the stems that were cut "contained food for the plant".

I have tremendous respect for @gardengal48 (PNW Z8/9) and she might be right on this point. I am simply pointing out that science suggests this issue is more subtle than you might think, and my idea is not being pulled out of thin air.

Your idea was not pulled out of thin air at all!! But it is somewhat outdated :-)) Horticulture is a science and like all scientific fields of study, data grows, changes and evolves with time. You will still see many references to pruning back before transplanting, just as you will about amending planting holes or painting or sealing pruning wounds. That doesn't mean these are still recommended practices, only that the current, updated information has not yet caught up to the authors.

@gardengal48 (PNW Z8/9) The studies I linked do not give opinions about best practices. They are just reporting the results of an experiment on hundreds or thousands of plants.

if its in significant stress/shock.. then you did it wrong... usually a timing issue ... perhaps if you had transplanted it in winter.. when it was dormant.. it could have grow some roots to support itself ... without you beheading the poor thing..

next time.. perfect timing.. and this wont happen ...

imo opinion.. rig up some shade for a moth or 2 .. to reduce sun stress in your area ...

water properly .. deeply with near drying before next deep watering ... drowning it wont help ...

next year.. if there is any die back.. prune it off then.. you are not God.. you can not know what to take off .... and beheading the thing.. will most likely take off a lot of stuff that will never die back....

ken

Root loss upon transplanting is on a continuum. From very little root loss to extreme root loss. For this theory to be validated, one would have to perform hundreds of transplants varying the amount of root loss.

And on the extreme end of 'root loss', it is common practice when rooting cuttings of many broadleaf evergreens to reduce the number of leaves to 2 or 3 and then clipping back the leaves 1/2. This is all to reduce transpiration while the cutting tries to push out roots. If too many entire leaves are left on, the cutting dies.