Overwatering a Japanese White Pine

I just started training a Japanese White Pine that I acquired early this year as nursery stock, and I'm afraid I'm in danger of losing it due to overwatering. We've actually had an unusually wet summer here, with frequent thunderstorms, which hasn't helped...of course it really comes down to me not being observant enough to let the tree dry out sufficiently.

Is there any way I can still save the tree? It has already lost some needles and the branches do not look great. I've heard of bare-rooting a tree and removing all rotted roots, but is this a safe thing to do with a pine? I realize my options may be limited; however if anyone has run into this problem and has suggestions, I would really appreciate it.

It seems I have a tough time working with pines...I wish this weren't the case . All of my other trees seem to like me!

1. You don't say where "here" is and you haven't indicated it in your profile, either. We need that info to give decent assistance. For instance, is it late summer where you are or late winter?

2. You also don't say whether the tree is still in its nursery pot and soil or if it is in a bonsai pot and soil. If the former, is it sitting on the ground where drainage might be an issue?

Pines don't care much for me, either, but if you can give this one better drainage you may be OK.

Yah me too. I just lost a little JWP that I acquired in June due to excessive water. Same situation in Maryland as wherever you are - a lot of rain, huge humidity and just general dampness. The soil mix it was in had degraded and was not very well draining, but given the time of year there wasn't very much I could do. In my experience once you can see pines begin to go downhill, they are dead trees walking as it were. I can spot the doomed infallibly from a subtle loss of glossiness and color change in the needles that happens overnight. Luckily it wasn't a tree with much potential or very expensive. You can try to improve the drainage if that is an issue by working a bamboo skewer into the soil and breaking it up gently. It didn't work for mine tho.

My Japanese maples aren't very happy with the situation either, but I haven't quite lost any of those, yet.

Sorry about this...I had thought that I'd included my location in my profile. I'll have to fix that!

I'm in southtern Ontario, Canada. Normally our summers here are hot and humid, but this year it has been really strange. It was cooler and drier than normal up until August, and then we got hit with A LOT of rain! Several areas in Hamilton, where I live, have had serious problems with flooding. Fortunately, I and my trees have been spared so far...that is except for the poor pine I mentioned.

Shortly after I acquired the tree, I transplanted it to a grow box made of cedar boards, with mesh screening in the bottom. I sifted some clay (Oil-Dri - akadama is far too expensive here), and mixed in some sifted fine fir bark. The mix was 75% clay to 25% fir bark. It seems to drain quickly, but the mix still retains a fair amount of moisture. I did no root pruning at the time of transplanting.

I may tree my hand at working with pines next spring. At least I know my wisterias and willows love this weather!

Yeah my wisteria has never been happier. Through hard bought experience I know A. palmatums and pines, in particular Japanese white pine are completely intolerant of poor drainage, for me at least. Water should fall through their soil as if you were pouring it through a window screen, and I still keep a bamboo skewer in the soil and only water when nearly dry.
Mike

I have used Oil-Dri in the past before I found a source for Turface. I find that it holds way to much water. I have lost a couple of trees because of that.

Ed

South Ont should be ideal for JWP. I should know coz I was born and brought up in Waterdown!
J

If you have actually planted in clay that could be the problem. It gets waterlogged and suffocates the roots.

I would try a late summer re-pot as you have nothing too lose imo.

Some and I stress SOME trees are happy with a late summer re-pot – JWP and mugo pine being two.

Remove the tree from the training box and inspect the roots. There should be healthy white tips showing.

If not, remove soil and dead roots gently to get back to firm roots. If there’s none there its probably a gonner anyways.

Re-plant in a 75% grit and 25% bark or peat mixture. Keep it damp and out of direct sun but in good light.

You should be able to get horticultural or turkey grit up around Waterdown off Hwy 6 or Connons on Hwy 5 just east of Waterdown. (we were all farm stock up there)
J

Prompt action might save the tree.

Root rot fungus is actually quite rare I belive but a recommended dose of a general purpose fungicide wouldn’t do any harm I’d suggest.

I have an article published by Harry Harrington at bonsai4me.com

http://bonsai4me.com/AdvTech/ATJapaneseWhitePine.htm

which covers early development of JWP. Not much of a tree but the theory is sound imo.

Healthy roots are shown below along with the beige fluffy looking mycelium fungus that is associated with these trees (amongst others).

Don’t mistake this for something more sinister.

Good luck and hope this helps.

TimR

Thanks TimR for the great suggestions...very helpful. I'm going to try the late-season re-potting with the mix you recommend...wish me luck!

Jeff

Hi Jeff,

We should check a few more points.

A little tree in a great big pot is generally a bad idea as the roots get swamped by all the damp soil.

Even a training pot shouldn't be any more than twice the diametre and depth of the rootball max imo.

JWP do lose some older needles late summer and can get a bit tatty looking. They go yellow and fall off eventually. These will be the needles furthest back on the branch nearest the trunk.i.e. the 2 and 3 year old ones.

General yellowing/browning of all the needles on a branch including the tip is therefore a much more serious sign.

Any chance of a picture?

thks

TimR

hi mountainrunner i live close by in beamsville
all my trees in bonsai pots are planted in coarse turface nothing else and they all do fine in all four seasons
i buy the turface in brampton at plant products they will sell to the public ithink the 50 lb bag is around 18.00 canadian hope this helps
andy



a mugo pine repotted this spring



i also tried oil dry which stayed way to wet

Thanks, Andy!

I'm going to abandon the Oil-Dri...it seems to be causing too many problems. Is it the Turface MVP or Turface Quick Dry that you use? I think you mentioned that you don't sift the particles...is this correct? If this works, it would save me a lot of time, not to mention money! There seems to be a fair amount of wasted medium using the sifting method.

Your trees look great...I'm so envious!

Jeff

hi mountainrunner yes it is turface mvp and i dont sift, i use it right out of the bag it is coarse enough for me
also when i repot i throw it in my growing beds (no waste)
hope this helps andy

Folks who grow BIG trees don't need to sift. The dust washes away quickly. I do mostly little trees, and I do sift -- usually. I use a kitchen flour sifter. I try to do it on a slightly breeze day, and I hold the sifter a foot or so above the bin into which I'm sifting. The fines fall more or less straight down, the dust blows away. I use the fines in my tiniest pots. Whatever stays in the kitchen sifter (most of it) goes into my "larger" trees' pots.

hi jim, i bet those tiny pots dry up pretty fast !!
do you keep all of your small stuff in a humidity tray ??