The perils of pinebark

[Tieball]

I use pine bark. particle size varies from 1/4” to 1/2”. Some chips and some what I’d call slivers. I've never had a problem.....however, all my trees are in wood grow boxes with ample drainage available. I have viewed my mix of pine bark, Turface and Lava in a plastic see through container (I was curious how it looked below the surface). Looked perfect for my use. Mixed well. Some pine chips were horizontal, some vertical and some random angle. And the Turface and Lava jumbled together very well consistently throughout the mix along with the Pine Bark that I could view.

 

[Adair M]

That's what I'm discussing too.

Again, if you can show me a piece of cardboard or relative-to-size chunk of wood washing down through a bowl of marbles, I'll believe you.
Or get yourself a bag of rice or beans and try to wash down some chopped onions to the bottom of a colander, without shaking the colander. The onions are more likely to move upwards as opposed to downwards. Unless you chop them so finely, that they'll pass through the colander as well; not an issue at all.

Also, if water hits a flat surface, like a horizontal piece of wood.. What would happen to the water? It'll flow off the sides, creating a gap facing downwards - if there are particles around it that are able to move - following the stream of the water. If the bark moves in that direction, it'll end up vertically. All 'follow the path of least resistance' comes into play and the bark will stay horizontal. Where it's suddenly packed between two layers of inorganic particles on both sides that keep it in place. It can't tumble over if there's no empty air pocket to fall in to. We try to prevent air pockets in bonsai as much as possible. The fact that the bark could've moved in the downwards facing gap to begin with, means there was an air pocket. That's two conditions that have to be met for a piece of bark to move to begin with.

We're not growing in bark alone. There's plenty of rocks in there too, they tend to keep things into place.
Two dimensional structures surrounded by two dimensional structures have the tendency to stack. If they're surrounded by three dimensional structures, stacking is very unlikely. Especially if the three dimensional particles are heavier than the two dimensional ones.

If you're comparing a water filled pond, littered with bark to a bonsai pot, you're forgetting the 70-80% pebbles that should surround the bark and you're replacing those pebbles with 100% water. That's not discussing particle shapes, it's discussing water flow and its effects on free floating two dimensional structures. That alone could be the title of a research paper, but it's a different subject. Bonsai soil is not water. The movement dynamic is entirely different.
I bet your filter is sucking in water straight from the pond, and it's not passing through a pebble bed (a three dimensional maze/matrix). Otherwise the pebbles would've stopped that bark from clogging the filter. It might be an idea to install such a contraption to prevent this from happening again in the future. I know those filter systems don't come cheap.
As a matter of fact, a well designed pond should have the pump behind such a feature simply to prevent these issues from happening. There will be other issues, like stacking on top of the contraption and eventually organic waste (if left long enough) will screw up the water flow. But it seems easier to scoop up a few pounds of pebbles with organic waste and hose those down, than to take apart a water filter and having to scoop the pond every time it rained. Waste water treatments have been doing it like this for over 30+ years. Here in Europe there is a growing community that do stuff like below for swimming pools, without chlorine. The 'aggregates' is what I mean with the pebble matrix or contraption/feature.
If you would have had a aggregate bed like below, the bark would still have stacked (a mix of two dimensional objects will likely stack), but it would've stacked on top of the aggregate instead of inside your filter. You could fix that with a shovel.

Gartenart | How does the water stay clean?

Lol!!! We’re getting off topic here, but I’m not worried about the pine bark stopping up my filtration system, it was stopping up my drain. The rush of the water going down the drain pushed the floating pine bark up against the screen. To the extent that the pine bark piled up. And lay flat against the screen. Then more layers of pine bark accumulated on top of those. And more layers, and more layers to the point the layers of pine bark were a couple inches high, holding back a pond full of water! Once I went over and removed the pine bark, the pond drain operated again. So, the power of those little chips of bark to suppress water flow was remarkable to me.

I believe a similar dynamic can occur in a bonsai pot over time. Less dramatic, for sure.

pond filtration discussion:

I have an up-flow bog in my pond. Take your diagram, and reverse the water flow, and you about have it. I have a submerged pump that pumps water into the bottom of a body of water. Above that body of water are three layers of gravel, large gravel, then medium sized, and finally pea gravel. Plants are planted in the pea gravel up top. Water is pushed from below up thru the gravel layers, up to the surface, where it then flows over a waterfall into the fish pond.

I have another pump that pulls the pond water thru the skimmer (where the bark has been accumulating) then it’s filtered with UV, and some of it goes to a biofalls and back into the pond, the rest goes up to the top of the bog to add additional water to the waterfall.

 

[Adair M]

I use pine bark. particle size varies from 1/4” to 1/2”. Some chips and some what I’d call slivers. I've never had a problem.....however, all my trees are in wood grow boxes with ample drainage available. I have viewed my mix of pine bark, Turface and Lava in a plastic see through container (I was curious how it looked below the surface). Looked perfect for my use. Mixed well. Some pine chips were horizontal, some vertical and some random angle. And the Turface and Lava jumbled together very well consistently throughout the mix along with the Pine Bark that I could view.

have you watered that daily, and left it outside for a year?

 

[Tieball]

have you watered that daily, and left it outside for a year?

Yes...to the boxes. Or...do you mean the see through container? If the container...no. I filled it with my components. Watered it. Emptied the water. Watered it again. Emptied the container. Let it dry out to examine. Not to scientific or consistent as a year of watering. However, my trees in the boxes with the mix are all doing perfectly fine year after year and they are all watered and stay outside all year long. No drainage problems with the boxes either.

 

[Adair M]

Yes...to the boxes. Or...do you mean the see through container? If the container...no. I filled it with my components. Watered it. Emptied the water. Watered it again. Emptied the container. Let it dry out to examine. Not to scientific or consistent as a year of watering. However, my trees in the boxes with the mix are all doing perfectly fine year after year and they are all watered and stay outside all year long. No drainage problems with the boxes either.

Well, that’s good for you!
All I’m trying to do is relate my experiences. Your mileage may vary.

 

[Cascading-Echinocactus]

I have had the same problem in the past using local un-composted (composted pine bark being less rigid, due to the loss of suberin through decomposition,holds more water and, for me, breaks down into a peat like consistency after a year) pine bark. The particles, after sifting, were all flat plates, unlike un-composted fir bark (which are more uniform with my other components). I saturate every time I water and have noted water rising slightly before draining properly. This is enough to keep me from using it in 1-1-1 mixes for my trees. In several pots i found individual plates impeding holes in the drain screen.

 

[Vance Wood]

I used to use pine bark and turface as my soil mix. And while I don’t remember “plugging” the drain holes being a specific issue, I did struggle with root rot. Perhaps I was (and still am) a chronic overwaterer. But, since I have switched to all inorganic soils with rounded particles, no more root rot.

But, life is full of perils. You can cross the road without looking left and right without looking and get away with it. For a while. Maybe.

the pond is fine, by the way. The filters will have it cleaned up in a day or two. The fish are happy!

I believe you struggled with root rot because of the Turface, which breaks down as well as akadama. It is important that you produce a soil mix that is structurally consistant for years. What usually happens is the structure breaks down and does not draing well while it contines to drain even less as it continues to break down.

 

[Cascading-Echinocactus]

I believe you struggled with root rot because of the Turface, which breaks down as well as akadama. It is important that you produce a soil mix that is structurally consistant for years. What usually happens is the structure breaks down and does not draing well while it contines to drain even less as it continues to break down.

I personally have never experienced, Turface MVP break down, even after repeated use, although I live in Alabama zone 8a I also know a few people that use it succefully in much colder zones. I'm assuming you have experienced Turface MVP breaking down; do you live in a lower zone with severe freezes? Did you use it as the sole component or as part of a mix? I believe you when you say it breaks down, I am very curious to know what conditions there would have to be in order for this to occur. The only negative experiences I've had with Turface MVP is when I didn't sift out particles under 1/8th inch. The mix held perched water which deprived the soil mass of oxygen and in turn root health suffered. This is not meant to come off as argumentative, I am genuinely curious as to why this happens to some people.

 

[Dav4]

I personally have never experienced, Turface MVP break down, even after repeated use, although I live in Alabama zone 8a I also know a few people that use it succefully in much colder zones. I'm assuming you have experienced Turface MVP breaking down; do you live in a lower zone with severe freezes? Did you use it as the sole component or as part of a mix? I believe you when you say it breaks down, I am very curious to know what conditions there would have to be in order for this to occur. The only negative experiences I've had with Turface MVP is when I didn't sift out particles under 1/8th inch. The mix held perched water which deprived the soil mass of oxygen and in turn root health suffered. This is not meant to come off as argumentative, I am genuinely curious as to why this happens to some people.

I lived in usda zone 6 MA and used turface back in the 1990's and early 2000s when winter was actually cold with January temps never getting out of the low 20s F for weeks on end and night time temps falling between -5 F and -10 F for a week straight. I never experienced turface breaking down, either, though I'm sure there was some degradation over time. Fwiw, once the water in anything freezes- at whatever temperature that occurs- further deepening cold doesn't worsen the freeze damage, meaning water is just as frozen at 20 F as it is at 0 F.

 

[mrt1]

I know, some of you love the stuff. And it’s a staple of many professionals. But hear me out. It’s really a problem...

it’s the shape of the particles. Pine bark is flat on two sides. Oh, when you first mix up your soil, their orientation is random. But, every time you water, you create a little flood of water from the surface down to the drain holes. And that water pushes on the bark. Moves it. Reorients it.

when that bark particle is pressed up against the screening covering the drain hole, it eventually finds a way to lay flat against it. The other pieces around it do, too. And the ones above. They orient themselves to resist the water, creating a flat layer, and stack themselves like bricks.

this creates an effective water barrier! Which makes the soil too wet, and can lead to root rot.

Last night, we had a gully was her of a storm. I use pine bark mini-nuggets in my landscape around my pond. Many got washed into my pond. They floated down to the skimmer, many were caught by the filter box, but some are smaller, and slip thru. My pond has a drain pipe behind the skimmer to drain off excess rainfall. The mini-nuggets fall down into the drain, and can plug it up. So, I fashioned a screen wire covering made out of hardware cloth, the same hardware cloth I used to use to make drain hole screens (before I switched to plastic). Well, the little pieces of bark would pile up against the screen. And so would the water! Oh, it still drained, slowly, but more and more pine bark would pile up, and the water level rose. Eventually, my pond flooded over. Held back by little pieces of bark.

if pine bark can cause a 6000 gallon pond to flood, I have no doubt it can stop up the drainage in a bonsai pot.

So just unfold a paperclip and pierce the drainage screens a couple times a year. Done.

 

[just.wing.it]

the issue I’m discussing here isn’t organic vs inorganic, it’s particle shape.

I've been using Fir Bark for 2 years now.
Its more of a cylindrical shape than a flat shape.....maybe it has to do with the shredding....
I get your point about the flat bark pieces.
I also would bring up the idea of a larger sized inorganic drainage layer to prevent clogging.

 

[roberthu]

I used to use pine bark and turface as my soil mix. And while I don’t remember “plugging” the drain holes being a specific issue, I did struggle with root rot. Perhaps I was (and still am) a chronic overwaterer. But, since I have switched to all inorganic soils with rounded particles, no more root rot.

But, life is full of perils. You can cross the road without looking left and right without looking and get away with it. For a while. Maybe.

the pond is fine, by the way. The filters will have it cleaned up in a day or two. The fish are happy!

Pine bark holds more water than usual inorganic soil like Akadama and turface. So maybe by not using pine bark you just don’t have too much water in the pots. Not necessarily because pine barks blocking the holes.

 

[Cascading-Echinocactus]

Pine bark holds more water than usual inorganic soil like Akadama and turface. So maybe by not using pine bark you just don’t have too much water in the pots. Not necessarily because pine barks blocking the holes.

Turface holds much more water than pine and fir bark.

 

[MichaelS]

If pine bark does't work, you don't understand it.
This tree has been in pine bark and gravel for 8 years now without repotting. https://www.bonsainut.com/threads/japanese-red-pine-not-a-bonsai.41268/
If you don't like this I have a white pine in a plastic pot that's been there for 6 years in park and gravel.

 

[SC1989]

I think too much bark with inorganic can be misleading. Lava rock, pumice etc. can look dry along with some of the bark, but the farther you go down, the more moisture sits in the bark. Looks/ feels dry , so it may get watered without actually needing it. I actually use some bark hunks in the bottom of seedling pots. A sprinkle to block the drainage, and it drains perfectly. I actually check it for moisture from the bottom more than the top. I prefer to use it on the bottom and only on taller pots. Never on flatter training pots.