AusBonsai

Hi,

Two of my pines, (one is a JBP and the other is a Nishiki and good size) have started turning brown. The new needles shooting out were green last week and are now all turning brown.

Both are still in growing pots. I bud selected a month or so ago and the new shoots looked great. Then suddenly they're browning. I haven't changed anything. They are on other ends of the garden from each other also.

I live in the Eastern Suburbs of Sydney near the cliffs. It has been very windy. Some of my maples have had leaf wind burn but pines are usually hardy to that.
Any idea what could cause it? What can I do?
I really hope they're not dying. The Nishiki was a 40th gift and was quite expensive.

Pics attached. Thanks for the help,
Jarren

Those brown shoots do not look good.
Dead new shoots can be either too dry (which can happen easily in spring as days and weather changes before we start thinking about dry) or conversely too wet which causes roots to rot so the plant cannot absorb water even though the soil is wet. The first is in a pond basket so unlikely to be saturated but drying is a definite possibility.
I note wires on the second tree. How long ago was it wired and bent? Only the top shoot on that one seems to be affected and it has a reasonably severe bend. Bending can rupture cambium and kill shoots, especially if you are a bit rough.

My assessment is 2 different issues here. first is probably dehydration and the second is a physical damage while bending.

The good thing is you still have healthy looking older foliage on both. Pines are quite good at new shoots from older needles so they will produce new shoots provided you can address the problems.

Let us know if either of my guesses are possible.

Thanks for the reply.

I have been watering every day because it's been really windy and somewhat sunny. I will check the soil and potentially water twice per day now.

The bigger tree with wire. I wired those branches probably 2-3 months ago. So I would have expected that it would have died sooner. Also, if it was the bend then the older needles would also have died.

I am hoping the rest of the tree looks healthy so it's just isolated.

Do you recommend removing those buds and dying needles? If it's se sort of pest it could spread?

I agree with what Shibui has said.

With root rot, I have had this issue; from my experience, it is as a result of being recently repotted in last 12 months and put into a larger container too quickly and the roots can't adequately dry out the soil and the soil retains too much water - everything looks to be going well until they are weakened for some reason (i.e. trimming, bending, dryed out on a hot day). As a result some of the fine new roots die, then next each time they are watered the rotten roots are sitting there trying to break down, and as they break down create a toxic smelling rotting mess (it can or smelt be seen until next year when it is safe to repot).

This is right up against the remaining reduced roots, which spreads into the healthy roots to the point where you have next to no live roots left.

I would be watering regularly to make sure it doesn't dry out again and it will also flush the toxins out of the soil. A pot on the ground retains more water than a pot up on a bench. Put it up off the ground on mesh - (i.e. fence mesh or a milk crate), this allow for maximum drainage as the soil is probably staying water logged. If you have a mound of sand then would also be similar to sitting on a mesh as it will provide additional drainage.

I would also spray with fungicide 3 times 2 weeks apart such as liquid copper.

I personally would not remove any foliage as it needs all it has to encourage the plant to move water from the roots to the needles and keep on drying out the roots.

If they survive I would repot late next winter.

Good luck.

I think you may have some tears which rotted.

When did you wire? When the wired growth was extremely green?

Also what’s your level of wiring skill? Beginner, intermediate or expert?

Thanks @tgooboon, good advice there. I'll elevate the big pot for better drainage.

@Daluke, I wired the Nishiki late autumn long before new growth appeared. The other branches have wire and seem fine.
Also, the smaller tree has no wire. That's what's strange. Two different plants, different pots but similar issue. Which leads me to believe it might be fungal.

Could it possibly be the fertiliser?

I'll keep regular watering and also spray a fungacide.

You need to eliminate all the possibilities one by one. First is to check the roots. Too dry = dead. Too wet = dead.
If it's not the roots then it maybe be an shoot fungus such as one of the needle cast diseases. A few of my white pines had this problem for the first time this year and I put it down to the relentless rain we have had this year. I sprayed them all with Chlorothalonil and they see to have recovered.

Thanks Mike. Good tip.
Hard to check the roots on the bigger pine because the pot is deep and it's actually quite root bound.
Side note - didn't repot because I was a little scared. I've lost a pine before from reporting.

The small one's roots seem ok, also a little root bound now that I've checked.

I'll try to source the Chlorothalonil.