Kiyohime advice..

[Bill S]

In my neck of the woods the sun effect is about that of August, sure can get a good burn in August. Matter of fact people lately have been asking where I went for vacation - yard work and running around for my job keeps me tanned almost all year, not bad for New England. Anyway yes the sun can cause damage now.

 

[rockm]

There is more than sun causing damage in August. It is a contributor, but only that. Overheated roots are a big cause of leaf and growth die back. Hotter nighttime temps and very little cool down on the root mass contribute to this stress--especially on non-native trees that haven't adapted to it.

 

[the3rdon]

I defoliated all the crispies, built it a little home that invites all morning sun and dismisses most of the sun after that.. Now I will wait..

Rock, I'm sure our weather is fairly similar and if I'm right our night time temps can very atleast 20 degrees from night to night moreso in July.. August tends to have a more average and even nightly temp, typically 65-72 degrees..In June and July it can very from 50-75 degrees at night.. Occasionally 80 at night..

 

[63pmp]

“It's amazing how people who are familiar with horticulture ignore local climate and location and common sense”

I’m adult enough to admit I don’t know everything. Perhaps you could explain to me the significance of local climate, location and where common sense is missing. You consider it’s important and I’m obviously missing the point, look forward to your reply.

Paul

 

[rockm]

"Perhaps you could explain to me the significance of local climate, location and where common sense is missing. You consider it’s important and I’m obviously missing the point, look forward to your reply.

Common sense indicates what works in Australia may not be the most appropriate advice for someone living in the Middle Atlantic states in the US. You're saying that local climate has no bearing on plant performance?

Local climate, including rainfall, sun exposure (and angle), overwintering, soil (we're not using the same soil ingredients--which has a big effect on cation exchange, etc.). Average temperatures also have a big bearing on root growth and damage, in both winter and summer. Wind exposure (including average prevailing winds) can also play an important part in leaf burn in particular.

"EC below 1000uS/cm for my Japanese maples (my regular fertilizer mix for JM is approx 350uS/cm"

This is mostly Greek to most bonsaiists, experienced or otherwise. It's simply not necessary to know it. Using a prepared commercial fertilizer, following the dilultions given by the manufacturer, you're probably in the safe zone. I don't need to know how much ethanol is in gas in my car's fuel tank, only that it keeps the car running. Some folks like to have that kind of knowledge, though.

 

[the3rdon]

Well, the tree is leafing out nicely and is doing well..

Don

 

[63pmp]

Thanks for your time and input, rockm. I see where you’re coming from, hopefully, you’ll see where I’m coming from, though, I accept we won’t agree on much.

Local temperature, rainfall, sunlight angle/intensity/exposure, overwintering, wind, soil temperature are all important for plant growth and when wrong produce visible symptoms in plants. I agree with you there. However, I know plant physiology doesn’t change from one country to another, and I think wind burn is as much a physiological and plant management problem as it is a local climate problem. I think we’ll disagree on this.

As for EC, well I suppose it is Greek to most people, much like cation exchange capacity and air filled porosity used to be. It won’t be until people in authority, ie, the bonsai guru’s, start talking about it that others will learn. So I don’t think dumbing it down because of peoples ignorance is a good argument. And I know appropriate EC levels is critical for healthy plant growth, this has been known in the horticultural industry for at least 50 years, no matter what your climate; so we’ll disagree on that one also.

I don’t think any off the shelf fertilisers are good, I don’t know about your local Home Depot ferts, so I’ll beg to lay off this to another time. This is another very large topic full of myths and bad information, and I know we’ll disagree on this also.

Thanks for responding, I see things a little differently now, I'll watch my posts.

Paul

The3rdon, glad your maples are improving.

If anyone's interested in my thoughts on leaf burn then feel free to PM me.

 

[rockm]

"However, I know plant physiology doesn’t change from one country to another, and I think wind burn is as much a physiological and plant management problem as it is a local climate problem. I think we’ll disagree on this."

I'd disagree about plant physiology not changing from climate to climate. Plants can adapt very well, some extremely well, to local conditions. JMs are no different.

Some trees are extremely good at adapting locally. I have a collected BC from Louisiana that remains dormant until well into April here in Va. when its brothers in the Achafalaya have been in full leaf for two months--and after warm spells that drive other trees here to push new growth. I've noticed Japanese maples aren't averse to adaptation, either. They will adjust to wet soil, as well as dry soil,-as long as the soil is consistently so.

Adaptation is a sliding scale. Some plants are wildly so, others not so much.

Yeah, leaf burn is certainly a consequence of plant management, but it's also a result of location, care and climate. It is neither one or the other. All are contributors.

As for prepared ferts being "bad," you're

 

[63pmp]

I'd disagree about plant physiology not changing from climate to climate. Plants can adapt very well, some extremely well, to local conditions. JMs are no different.

Yes, they do adapt well, which is why we can take plants from one part of the world to another. Within reason of course, it is difficult to take a rhododendron from Tibet and expect it to grow well in Adelaide for instance. In this case management of micro-climate, light intensity, etc., plant husbandry, for want of a better term, is important. My point is that the basic physiology doesn’t change. How the plant absorbs moisture and nutrients through the roots remains the same, how it photosynthesis, builds cell walls and other cellular structures, how it lays down wood, produces lignin, respires, etc, these physiological functions don’t change. And while there is flexibility (there adaptability), an example maybe in the amount of chlorophyll in the leaf, the basic physiology, how they do what they do, even down to the atomic level, remains the same. Where they fall down is when there physiology cannot cope. eg (NOTE: this is a made up example, its probabaly not true) the normal waxy cuticle on the surface of a rhodo leaf is too thin and when planted in Adelaide cannot cope with the low humidity and there leaves dehydrate. (NOTE: This is a made up example, its probably not true)


I've noticed Japanese maples aren't averse to adaptation, either. They will adjust to wet soil, as well as dry soil,-as long as the soil is consistently so.

How well do they do in comparison to each other? I first became intrigued with this subject when I noticed my trident maples in the field did much better than my potted ones. It’s common knowledge field grown plants do better. But the field tridents are in direct sunlight from dawn to dusk, they get everything thrown at them and no signs of windburn, yet my mollycoddled trees in growing pots often show signs of stress, windburn; all sorts of things. So then I started asking question like. Why is it windburn does not cause the leaf to wilt, or even wilt only a little bit or show other signs of water stress? If the leaf stays upright it’s getting enough water right? If wind burn is caused by the leaf not being able to supply water to those end bits, why is it they don’t wilt, only die off? How is it tridents in my field never get windburn? There the same genetically, their cuttings from the same host plant. The difference is, obviously, in the way I look after the plant, what am I doing differently? That’s when I started to study up on fertilizer and water quality and plant physiology.

Adaptation is a sliding scale. Some plants are wildly so, others not so much.

Yes, I agree with you here.

As for prepared ferts being "bad,"

Really don’t want to talk about this, but it’s about accepting what is a balanced fert and what’s not. And what is missing from the ingredients label.

Paul

 

[rockm]

"I first became intrigued with this subject when I noticed my trident maples in the field did much better than my potted ones. It’s common knowledge field grown plants do better. But the field tridents are in direct sunlight from dawn to dusk, they get everything thrown at them and no signs of windburn, yet my mollycoddled trees in growing pots often show signs of stress, windburn; all sorts of things. So then I started asking question like. Why is it windburn does not cause the leaf to wilt, or even wilt only a little bit or show other signs of water stress? If the leaf stays upright it’s getting enough water right? If wind burn is caused by the leaf not being able to supply water to those end bits, why is it they don’t wilt, only die off? How is it tridents in my field never get windburn? There the same genetically, their cuttings from the same host plant. The difference is, obviously, in the way I look after the plant, what am I doing differently? That’s when I started to study up on fertilizer and water quality and plant physiology."


The single biggest thing you're missing here is the container your tridents are in. Their roots are subject to a great deal more than the roots of trees in the ground (regardless of cloning). Temperature swings in a pot are huge--I've got trees that face a 40 or 50 degree swing from evening to afternoon. Temps on the sides of pots can reach 120 F in full sun. This all has a terrific effect how how roots in the container perform.

The containerized trees don't have nearly the resources to draw on as their inground cousins. In particular, they have about 100th (and that's a conservative estimate) of the root mass as a tree in the ground. That means they simply can't take up nearly the same moisture. Since the soil volume in a container is miniscule, they can also be subject to any small breakdown in the soil structure which will affect their abbreviated root mass more quickly.
And for the thought of trees being "mollycoddled" in pots, that simply wrong. Their environment is a hundred times more demanding than a nursery bed. It's even more demanding if the person caring for them tries to "mollycoddle" a tree. Too much care results in tree death. It's one of the major causes of ex-bonsai...

 

[63pmp]

“The single biggest thing you're missing here is the container your tridents are in. Their roots are subject to a great deal more than the roots of trees... ... in full sun. This all has a terrific effect how how roots in the container perform.”

Yes, that’s exactly right. We take a tree from a region of Japan and stick it in a pot in another part of the world, and wonder why it doesn’t do so well. We then learn to modify its environment to suite it, in other words, compensate for its physiological limitations. We do all the suggestions that have been mentioned earlier in this thread. We put the plant in afternoon shade or in a shade house; improve the soil to allow oxygen to the roots; we try and keep the pot and root ball cool; ensure it doesn’t dry out And what are the physiological implications of these practices on the plants? Placing the tree in the shade reduces leaf transpiration; it also slows growth, and depending on where it is, can lengthen internodes. This is not necessarily the best solution. Improving root oxygen is critical, plant roots die without oxygen. Root temperature is critical because at some point over 40 C proteins in root cells stop functioning, and so does the root. More oxygen and cooling are very good things to do. . We do all this and sometimes we still get windburn. Huh? What’s that about?

What I find weird, is that while bonsai practitioners accept that low oxygen and high temps cause real physiological effects on their bonsai, there is reluctance to even consider the third, just as important, factor which effects water uptake by roots, something which also varies day by day.

That thing is salinity.

Roughly, this is how it works (simplified version). Roots absorb water by osmosis. Water has to move through the structural wall components of the root to get to the cells that make up the xylem before getting sucked up to the leaves. Water (and nutrients) can do this because a concentration gradient exists between the outside and the inside of the root. The solution inside of roots has some salt and a large amount of sugars dissolved in it, the outside has not, water moves into the roots due to this concentration gradient. (put a dried up sultana in a glass of water and watch as it swells up, it’s the same with roots) As the salinity of the outside solution approaches the concentration of the inside of roots, the flow of water reduces. This happens all the time to plants, it rains and the soil becomes saturated with a low salinity solution. As the soil dries out, the salinity increases, but it happens at a pace that plants can easily adapt to, they increase the sugar concentration in the roots. At some point plants can no longer compete with outside forces and do not take up any further water and so growth stops..

There is another problem in that most saline solutions have an excess of one or more ions, plants may unintentionally take up too much of that ion. Sodium is the obvious example. Plants have little capacity to store these extra ions. They can’t put them in cells because they disrupt cellular metabolism, they can’t store them in roots as they disrupt water and nutrient transfer, they can’t store them in wood because of the above cellular reason. So they store these excess salts (ions) in the spaces between cells in the ends of leaves. This is what causes windburn, the salts which have a high water need prevent water moving to the cells in the ends and edges of leaves during high water demand. And/or the salt concentration reaches a point which is toxic to leaf cells. This is why wind burnt leaves do not wilt. A good way to stop persistent windburn is to reduce the salt load the plant has to deal with. Which means watching the salinity of water and fertiliser.

"And for the thought of trees being "mollycoddled" in pots, that simply wrong."

Mollycoddle would have to be one of the most subjective terms in the English language, you will never get consensus on what level of attention is considered mollycoddling. One man’s mollycoddle is another man’s abuse. Not much point debating this point.

Paul

 

[John Ruger]

Well, if salinity levels is the case with regard to leaf tip burn, then calcium and magnesium would reduce sodium toxicity. Would not the symtoms first materialize on older leaves? It could take weeks (at the minumum days) in order to accumulate concentrations high enough in order for symtoms to manifest.

 

[63pmp]

Well, if salinity levels is the case with regard to leaf tip burn, then calcium and magnesium would reduce sodium toxicity. Would not the symtoms first materialize on older leaves? It could take weeks (at the minumum days) in order to accumulate concentrations high enough in order for symtoms to manifest.


Calcium inhibits sodium uptake uptake, yes, rule of thumb it's a 2:1 ratio Ca : Mg. Symptoms of excess salinity are seen in older leaves first, crisping around the edges and then the leaf dies back from the edges, eventually they fall off.

Wind burn is somewhat different in that it happens quickly, plants cope with salt levels which are sub-toxic until transpiration increases the salt concentration in the leaves to toxic levels. The idea of diluting fertilizers to half strength in summer relates to this. However with Japanese maples their low level of salinity intolerance means that even half strength may be too high. It depends on the fertiliser and water quality. Transpiration rate is also a factor, plants have been burnt indoors due to air conditioners creating a very low humidity and salt built up in leaves becomes toxic due to the rate of water loss, so reducing transpiration by increasing humidity or cooling leaves is good on excessive hot or drying days (its just not a great long term solution).

Thanks for your interest.

Paul

 

[John Ruger]

Then I assume that if the soil is well drained, irrigation will flush out the salts and/or chloride accumulated within the root zone. Correct me if I am wrong, you are stating that there are sub-toxic salt levels that will in essence increase to toxic levels as a result of increased transpiration during periods of excessive heat? If this is the case, then do sodium ions develop leaf burn symptoms when water is sprayed/misted on leaves?

A popular idea follows the notion that if one mists bonsai leaves during periods of intense sun, then the result may lead to leaf scorch. I tend to believe that not enough heat can be generated within water droplets to cause that type of damage, so do you beleive that these are actually incidences of higher water salinity?

 

[BUBBAFRGA]

BlackBerry= cigeratte pack

So blackberry is the new cig pack? LOL

Most time its my Blackberry that is taking the picture....

 

[63pmp]

John,

Flushing the soil periodically will remove soluble salts that can accumulate in soils, watering so that there is minimal runoff will cause salts to accumulate. It is advisable that once a week during hot drying weather to really soak the soil so that water pours out of the bottom of the pot for a minute or so. This will flush accumulated salts out.

Correct me if I am wrong, you are stating that there are sub-toxic salt levels that will in essence increase to toxic levels as a result of increased transpiration during periods of excessive heat?

Yes, this is correct. Each species of plant is different as they tolerate different ranges of salt concentrations. However they have their limits. Transpiration is mainly about cooling leaves on hot days, water is evaporated inside the leaf, cooling it. Minerals are brought up in the water from the roots and can collect in the leaf as water evaporates. When fertilising heavily and/or the fertiliser is unbalanced than it is also possible to collect salts this way, this can happen with spring feeding, once hot weather hits the leaves can no longer cope with the salt load.

The simplest way I’ve found to combat sodium in my irrigation water is to sprinkle gypsum on my pots, I do this every few weeks or so, depending on how much I’m watering. I add extra magnesium to my fertiliser solution to avoid magnesium deficiency.

A popular idea follows the notion that if one mists bonsai leaves during periods of intense sun, then the result may lead to leaf scorch. I tend to believe that not enough heat can be generated within water droplets to cause that type of damage, so do you believe that these are actually incidences of higher water salinity?

Water droplets on leaves do not cause burn. The thought is that the droplet acts like a lens. If you look at a droplet you will notice it is only ½ a lens and will not focus sunlight to a point, also, water evaporates off the leaves, cooling the leaf underneath it. Spraying leaves with water that contains sodium (and some other elements) can burn the leaves, yes. I’m not sure what concentration would be required, my water has about 60 ppm sodium and it doesn’t cause leaf damage when it’s sprayed on leaves.

Paul

Here's a picture of a salt damaged maple leaves, there is also weevil damage to the bark of this stem.

 

[John Ruger]

That's some fairly substantial damage; more than what I've seen. Was this your tree and if so, how did you correct the issue?

 

[63pmp]

John,

It’s not much of a story, so I’ll try and keep it brief.

The salt burn occurred when I changed my irrigation water from an old spring to a new well dug last year. About the same time I also decided to change my fertilisers, previously I had been using fish emulsion, but that got too expensive, so I swapped over to a chemical fertiliser. It wasn’t long before I started getting burnt leaves on maples and hornbeams. So I started reading books and searching the internet for answers. In a previous job I worked as a soil analyst, fortunately I still had an EC meter, one of my books had a table of sensitivities so I started measuring my water and fertiliser mixes first. Decided they were too high and reduced fertiliser concentration. This helped with the salt burn but it wasn’t long again before I started getting very strange looking leaves.

Here’s a photo of some weird leaves on a trident and J maple.

http://www.bonsainut.com/forums/attachment.php?attachmentid=12359&stc=1&d=1276326569
http://www.bonsainut.com/forums/attachment.php?attachmentid=12360&stc=1&d=1276326569


More research and I concluded the new problem was calcium deficiency. I then decided to look at fertilising in depth and soon discovered the problem was my fertilisers were very poorly designed. I looked about and found that virtually all fertilisers sold in Australia are designed for gardens, not pot plants, even those that say they’re for pot plants aren’t. So I had to start mixing my own chemicals. I developed a program of using gypsum on the pots to combat the sodium in the water, and a fertiliser based on Steiner’s ratios. I found hydroponics provided a lot more relevant information than soil oriented books. This is because I think, growing bonsai is very much like what hydroponic growers call soilless media-drip irrigation. Steiner’s theory is that plants can adjust to ratios of cations and anions that are not typical of their normal uptake characteristics, but that plants will expend much less energy if the ions of the essential elements are in a proper balance. It explains why plants will grow in different nutrient solutions, but do better in some and not others. I found the Steiner ratios provided a nutrient solution with a low EC, about 370 uS/cm, which I felt was good for my maples. I have been using this solution since January and my maples have done very well.

Paul

Here’s a photo of leaves after treatment with gypsum on the soil and new fertiliser mix. You can see where plant growth came to a halt with Ca deficiency and then took off again with gypsum and low EC fert.

http://www.bonsainut.com/forums/attachment.php?attachmentid=12361&stc=1&d=1276326569