defoliation - what does it work on?

hi,

i have been looking at my deciduous trees in relation to the wonderfull foliage and ramification results that get posted with premna, ficus etc and it got me wondering - can we collectively create a definitive list of species that respond very well to total defoliation and equally importantly those species that it does not.

I think its best if we only post species that we have total personal experience of, so no urban myths creep in that people my follow and ruin their trees.

i have had personal success totally defoliating acer palmatum un-named species , acer pal mikawa yatsubusa, trident maple, chinese elm, & bouganvillia.
i had no good results with European or white beech but my timing may have been wrong

i would like to know about anyone trying acer kiyohime, cotoneaster, blackthorn.

thanks Marcus

I'll chime in:

I have had good luck defoliating Fagus grandifolia, during a non repot year, but you must leave the terminal leaf on each branch (to draw sap) and the results will be the breaking of adventitious buds on the trunk and branches, this technique does NOT reduce leaf size, it simply prompts budding.

I defoliated Euonymous and the thing sulked for a month and then only broke the very terminal bud on each branch...bad idea. I wont do it again.

My Bougainvillia self defoliates every spring and throws a branch at the former union of every dropped leaf.

-Jay

Marcus, first question..why you want to have them defoliated; and second..what do you mean by no good result on beech ?

From my experiences with deciduous trees, not so many which do not like defolaited; one that I know is Pemphis which sometime may cause dying, and ficus benyamina which may cause dying back if not carefully handled.

drgonzo wrote:I'll chime in:

I have had good luck defoliating Fagus grandifolia, during a non repot year, but you must leave the terminal leaf on each branch (to draw sap) and the results will be the breaking of adventitious buds on the trunk and branches, this technique does NOT reduce leaf size, it simply prompts budding.

I defoliated Euonymous and the thing sulked for a month and then only broke the very terminal bud on each branch...bad idea. I wont do it again.

My Bougainvillia self defoliates every spring and throws a branch at the former union of every dropped leaf.

-Jay

If I may understand why Marcus wants to defoliate deciduous trees is for the remification forming purpose. This is the technique I normally teach..only with sufficient defoliation, you can practice the clip-and-grow in proper way, because you can see the structure clearly and can work on them. But it doesn't mean you need to defoliate every single leaf unless yo want to display the winter nuance as the Chinese does.

So, defoliation will never been a bad idea, if it does not reduce the leaves size, it will not make the leave bigger. Plant phisiologically speaking, if you work properly on the ramification structure, every defoliation will reduce certain size of the leaves from the new twig section.
But defoliation doesn't make sense if not for forming the ideal ramification structure... Most people tend to prun their deciduous bonsai like a hair cut without working on the ramification, that's why many deciduous bonsai look oweful when the leaves drop in winter or when defoliated... they do not look like nice mature tree in nature...

Does not work on crabapple. Works on trident maple. Limited results on Acer rubrum. Works well on Korean hornbeam.
Iris

I should have expanded my reasoning, I find defoliation is a "bad idea" if the tree responds so poorly to the technique that its resulting loss of vigor puts its health or its life in danger. As It did with my Euonymous.
-Jay

@drgonzo Euonymous have only one growth spirt per growing season this is why defoliating them is dangerous ... I believe this is also true of fagus so it is interesting to hear about leaving a sap drawer....



I have used defoliation on many acer ginnala and it works well. matter of fact I defoliated one of mine 2 times this year. leaf size reduces well in shohin trees also.

defoliated Tridents of course you almost have to to keep them under control.

partial defoliation of korean hornbeam (i've never gone full out yet) and partial defoliation on japanese hornbeam (including cutting the leaves in half) both of these lead to back budding and leaf reduction.

Bougie gets defoliated every spring a) so I can wire b) helps with leaf reduction.... [note: if you aren't using Bougain fert ....get some]

Acer P defoliated with good results

ang3lfir3 wrote:@drgonzo Euonymous have only one growth spirt per growing season this is why defoliating them is dangerous ... I believe this is also true of fagus so it is interesting to hear about leaving a sap drawer....

I am actually considering writing an article about my work with F. Grandifolia expanding on what Harry Harrington has already written about F. Sylvatica that would include internode reduction, branch planning, back-budding, and leaf reduction techniques, I'm going to begin photographing all the steps I use next spring and then add my written copy when I get time, perhaps Bill V. or ABS bonsai magazine would be interested in it.

Marcus and I have both bemoaned the lack of information regarding Beeches in general, most notably absent from bonsai literature is F. Grandifolia, a species that despite what has been assumed about it, responds very well to bonsai culture. Once I become a bit more confident in the success of the techniques I'm applying I will share them with anyone who's interested in the community, I have a great affection for F. Grandifolia and the large specimen I am working on now as well as my forrest planting of the same species are among my most treasured trees.

As for my Euonymous, with rigorous pruning I could get say one or two more flushes out of the tree after the first main flush, but each successive extension became weaker than the one before it, I also found them very unwilling to backbud on old wood if there were ANY buds further out on the stems that would be easier for the tree to break, so I chopped off all the main branches a week ago to rebuild a better canopy next year.

-Jay

Robert Steven wrote:Marcus, first question..why you want to have them defoliated; and second..what do you mean by no good result on beech ?

If I may understand why Marcus wants to defoliate deciduous trees is for the remification forming purpose. This is the technique I normally teach..only with sufficient defoliation, you can practice the clip-and-grow in proper way, because you can see the structure clearly and can work on them. But it doesn't mean you need to defoliate every single leaf unless yo want to display the winter nuance as the Chinese does.
So, defoliation will never been a bad idea, if it does not reduce the leaves size, it will not make the leave bigger. Plant phisiologically speaking, if you work properly on the ramification structure, every defoliation will reduce certain size of the leaves from the new twig section.
But defoliation doesn't make sense if not for forming the ideal ramification structure... Most people tend to prun their deciduous bonsai like a hair cut without working on the ramification, that's why many deciduous bonsai look oweful when the leaves drop in winter or when defoliated... they do not look like nice mature tree in nature...

hi Robert,
i am looking at defoliation to improve the strength of inner weak twigs, or to get buds to open on inner areas of a bare branch, rather than for display. Once these inner areas grow I often cut off the outside sections of branches that have poor taper or un-natural bends, then i can regrow the branches in a better way.

There are several reasons for my question , i sometimes manage to buy a nice, old bonsai for good price because they have been neglected or pruned badly, so all the leaves are on the branch ends only. These trees have great trunks, signs of age, but need to have branches that match the mature look of the rest of the tree. Another reason is to actually keep the inner growth and twigs alive once they have formed on trees in the next stage of their development..Just Leaf reduction is not my aim, most of my trees are quite large and still developing so the leaves may reduce over time as the ramification increases, or they usually reduce as the time between repotting is increased on a more refined tree.

re Beech, On an experiment tree I removed all the leaves in mid summer - no buds opened until the next spring ! the following year i tried the same method on the same tree - same result.
re White beech (crenata) - i had an experimental tree and defoliated all inner leaves, leaving just the end leaf so the terminal bud stayed dormant. The tree stayed like this until winter - one single leaf on the end of every branch !, none of the inner buds opened. (same result next year too) -this method is accepted as a 'normal beech' tree method so i was trying it on the crenata to see what happened

thanks to all so far,

marcus

Please read the latest Bonsai Focus magazine with Japanese Shohin expert Tomohiro Masumi, who shows why not to totally defoliate deciduous trees for better ramification. It doesn't work that way. You need to have larger leaves left back at the tip of the branches to take energy from the inner parts when these are trimmed. This will decrease the length between leaf pairs and develop better and tighter ramification.
Total defoliation will weaken the overall health of the tree, but is sometime done in order to sort out the branch structure on larger pruning operations. But the tree will react with strong growth totally leaf defoliated, making longer growth and looser ramification as result when done, which then have to be corrected afterwards.
(Cant show it here, because the article is copyright protected).

Regards
Morten Albek

I'm noticing responses from people spread across some 4000miles here. Surely different climates need to be taken into account in defoliation?

Thanks for the additional info Jay.

Marcus, good reason and fully agree. Despite of species and climate, different purposes need different handling...

fiona wrote:I'm noticing responses from people spread across some 4000miles here. Surely different climates need to be taken into account in defoliation?

You are right Fiona.

Here in the tropics, defoliation works very well in developing finer ramification and developing smaller leaves as opposed to what Morten had posted which might be true for most deciduous in the colder climate.


regards,
jun

fiona wrote:I'm noticing responses from people spread across some 4000miles here. Surely different climates need to be taken into account in defoliation?

The only climatic difference I've noticed is that in North Florida, where I used to live, I could defoliate my trident maple 3 times a growing season. Here in NC, I can do it twice a season. Farther north the rule would be once.

I was told and have followed that advice that if you want to improve ramification of the interior of a tree it is best to remove the end buds from every branch and major branchlet. It seems to work for me.

On other than tridents (and sometimes willow-leaf figs) I usually only do a partial defoliation to stimulate growth in weaker areas of a tree. Again, other than my two little figs, I never defoliate broadleaf evergreens.

morten albek wrote:Please read the latest Bonsai Focus magazine with Japanese Shohin expert Tomohiro Masumi, who shows why not to totally defoliate deciduous trees Regards
Morten Albek

Hi Morten, thanks for the additional alternative information - i dont have the article here right now but will check it out asap. my observation of shohin techniques is that they can be quite different to the methods that work on large and extra large bonsai - i certainly believe the larger trees have much greater reserves of stored energy and can both cope and respond to harder bonsai methods. the shohin i see are often in proportionally much smaller pots (by ratio to trunk size) than larger trees, so i can see that some of these trees could have a harder time building inner strength -( but the best collection of shohin tridents in the UK are defoliated 3 times a year and look unbelievable, but the owners are very good at it and feed feed feed)

thanks

Marcus

fiona wrote:I'm noticing responses from people spread across some 4000miles here. Surely different climates need to be taken into account in defoliation?

hi, not really Fiona in context with the original question - to create a definitive list of species that have responded well, and those that have not. As we are seeing though the climate can effect the length of the growing season, so it is effecting when, or how many times the tree is defloliated, so while the location of the posts must be considered as you say, it does not seem to be effecting which species people are trying it with.

The beauty is by having worldwide responses we may find some species that respond in their optimum locations and struggle on the geographical limits of the species, so helping us decide on our actions with our trees.

i did a black pine for an experiment last year - just as the buds were extending i cut off every outer strong candle and removed every needle on the tree - very interesting result - every bud on every branch became a medium strength candle with short 4cm needles - i wouldnt do it every year, but you wouldnt need to.

regards Marcus

Hi Marcus
I have not many deciduous trees. But defoliation works well for me on Acer campestre, Acer palm.
Gretings Pavel

Pavel Slovák wrote:Hi Marcus
I have not many deciduous trees. But defoliation works well for me on Acer campestre, Acer palm.
Gretings Pavel

Hi.
I feel Acer Campestre is an easy species for bonsai but should never be defoliated completely.
For me acer in general should have the opportunity to harden off their leaves first for 4-6 weeks to gain some energy.
Sunip