Exceptions to "top pruning is bad" for collected conifers

[NaoTK]

Why is top pruning bad for collected conifers? People say "conifers get their energy from their leaves/needles" but what about a collected tree with a reduced root mass that is unbalanced to the top? I imagine the tree would collapse if you kept all the leaves, but pruning might restore the balance while the root mass recovers. I understand more leaves would generate roots faster, but not if the tree dries out from transpiration first. I know folks build humidity tents for this reason.

If I collect a conifer but only got 50% of the root mass, would pruning off 25% of the leaves offer an advantage?

 

[PaulH]

Depends entirely on the species. Only on junipers and do I leave as much foliage as possible. Junipers have the ability to absorb water and hydrate from the foliage so newly collected junipers must be misted multiple times a day as they regenerate roots. Other conifers should indeed have the foliage balanced to the roots.

 

[Hartinez]

I think paul nailed it. Junipers are the rule here in my opinion. But on extending species like Englemann or Doug fir id imagine you Could remove said foliage percentages and it would have just as much chance of survival as not. Regardless though, on any newly collected tree, I have been conviced that the foliage, even on junipers is not nearly as important as the quality of root ball and associated field soil. I have no science to back any of this only anecdotal evidence with my own experiences.

 

[Kanorin]

Last winter I collected two shortleaf pines (echinata). The one that I reduced its foliage (~40%) lived. The one that I left foliage intact did not make it. Need more n, but I know which way I’m leaning.

 

[andrewiles]

I've collected quite a few subalpine firs, engleman spruces, mountain hemlocks and western larches over the past few years. My experience has been that if I don't remove top foliage and don't mist I can only successfully collect trees that have good rootballs. Natural rock pockets, etc.

With automated misting and top reduction I can collect a much wider set of trees with poor roots. Or I can do more rootwork at collection time to reduce work down the road. Or I can collect at non-optimal times.

I often take 50% off the top and only get 20% of the fine roots. Wild guess on the latter, but if anything I get fewer roots than that.

I imagine with more top foliage trees can recover faster, but as you say it doesn't much matter if they're dead.

 

[NaoTK]

Thanks for your replies everyone, sounds like we are on the same page here. I will try some light top pruning this year. Yet various pros still say to keep all the foliage. I will ask every pro I know at the pacific bonsai expo this question and report back.

 

[Maiden69]

I know Ryan constantly say for junipers keep, as that is one of the species he works the most that are collected, but I haven't heard anything about pines. What kind of conifer did you plan to collect? I think maybe the saying pines strength is in the roots and junipers in the foliage could apply to this?

 

[woodkraftbonsai]

I had one pine this year that I feel would have survived IF I had topped some of the foliage. My theory was that the tree did not have a good balance between the foliage and roots - this conversation just goes to further my belief in that theory. Thanks for bringing it up!

 

[MrFancyPlants]

I try to leave as much foliage as possible with one exception. If there is a large runner or trunk above what your final tree is to be, I’ll cut off the top for stability. Stability is important for reestablishing roots after collection. You wouldn’t want it swaying in the breeze at that point.
Not, that I have a ton of experience collecting, FWIW.

 

[NaoTK]

I have been collecting englemann spruce, mountain hemlock, subalpine fir and have had great success without pruning, but I also got most of the root ball. But last year I got a spruce with few roots and it later died.

This week I collected a couple questionable spruce (I decided the plural of spruce should be "sprice") and I just went out and top pruned them. I have too many trees and am happy to experiment.

 

[InstilledChaos]

From a physiology standpoint the science (as applied to landscape plants) say to keep all the top growth. Pruning the top growth leads to hormonal signals to replace solar panels at a time when you want all the energy driving root recovery. In addition, obviously less leaves means less energy for root growth. The scientists who advocate this approach say that if there is an imbalance the tree will shed the least energy positive branches and keep the most beneficial. Obviously, in bonsai we may not want to leave these decisions to the tree, so there may be instances when we want to proactively make those cuts. However, this is why I tend to lean on the side of not touching the top if at all possible.

 

[sorce]

I think the reaction to the action, what and where you are cutting, is more important to think about than just to cut or not.

Cutting every next year's fat juicy leader candles isn't the same as removing a bunch of interior needles, or even one whole half of a tree.

I am a "leave it onner".

I don't believe a tree will transpire what's not there. So I don't think "imbalance" is real in this instance.

Sorce