De-‘candling’ and pests?

[ACooke]

Hi all,

Couple of newbie questions here.

Firstly, it’s late Autumn here in Sydney for those in the northern hemi.

Perhaps the easiest; can i/should i prune some of these buds to prevent whorls forming? I’m aware of the decandling/shoot selection technoques but are these too under-developed? Most see to select between actual shoots rather than these are this coming springs new buds?
The tree’s still in early development but due to pre-existing whorls/swelling i’d like to keep a few trunk-paths and lower branch options open/whorl free. Should i thin this out now before further growth and energy is expended on so many buds?



The other question refers to 2 different JBP’s i have in different locations and soils. Any suggestions as to what may be causing the yellowing/occasional ringing; and perhaps more importantly the clumped ‘cut’/died back needles?



Also the larger one in particular has (below) predominantly 3 and even 4 needles per wrapper it seems, but only on some of this years candles; is this odd?



Some notes; Its rained extensively here in Sydney the past month and it’s possible i may have over fertilized (although i wouldn’t have thought so?).



They’re both in garden beds so can’t really be moved from the rain.



I also noticed a bunch of centipedes (not curl grub) about, however i couldn’t visibly see any other pests about.



Any advice as to whether i should be concerned and if so, what might be a good course of action?

Thanks all; and sorry for the tedious newbie Q’s.

 

[Deep Sea Diver]

Hi all,

Couple of newbie questions here.

Firstly, it’s late Autumn here in Sydney for those in the northern hemi.
View attachment 547239
Perhaps the easiest; can i/should i prune some of these buds to prevent whorls forming? I’m aware of the decandling/shoot selection technoques but are these too under-developed? Most see to select between actual shoots rather than these are this coming springs new buds?
The tree’s still in early development but due to pre-existing whorls/swelling i’d like to keep a few trunk-paths and lower branch options open/whorl free. Should i thin this out now before further growth and energy is expended on so many buds?

Might want to at least take these down to two buds in the next months when you feel comfortable doing so. Could even wait until late winter given they don’t extend much. We leave two equal length buds with a tight, roughly 30-40 degree separation. This will give time to decide.

The other question refers to 2 different JBP’s i have in different locations and soils. Any suggestions as to what may be causing the yellowing/occasional ringing;

The spots and ringing sure looks like the start of a form of needle cast. Happens frequently, especially on trees rarely pruned and low ventilation.

and perhaps more importantly the clumped ‘cut’/died back needles?

We have a bug, a sawfly, here that will chomp the needles… so check for caterpillars (sawfly larvae or equivalent, if they are in your area. Also rabbits will nibble conifers like this.

Also the larger one in particular has (below) predominantly 3 and even 4 needles per wrapper it seems, but only on some of this years candles; is this odd?

3-4 needles per bundle can happen, especially trees with rapid growth.

Some notes; Its rained extensively here in Sydney the past month and it’s possible i may have over fertilized (although i wouldn’t have thought so?).


They’re both in garden beds so can’t really be moved from the rain.

I also noticed a bunch of centipedes (not curl grub) about, however i couldn’t visibly see any other pests about.


Any advice as to whether i should be concerned and if so, what might be a good course of action?

Other than candle thinning and general pruning to allow better ventilation, not really. Might want to check around to see is a safe product is sold in your area for needle cast. @Shibui likely would know best. You can PM him if you desire.

Thanks all; and sorry for the tedious newbie Q’s.

Not to worry,

Cheers
DSD sends

 

[Shibui]

Yellow/brown rings around pine needles is indicative of Dothostroma AKA needle cast. It's a fungal infection that attacks in wet weather. Previous damage can't be cured but you can prevent more infection by using fungicide through spring (and summer if you are watering the foliage or have a wet summer). Copper based sprays work well.

Not sure about the chomped needles. We don't have the same pests as USA so very little that actually eats pine needles down here. Case moth caterpillars could be using them to build their protective homes. Would not think rabbits would be a problem in Sydney? Can't think what else might eat pine needles.
Centipedes don't normally hang out in bunches and they are carnivores so not interested in your pine needles. Maybe you saw something else but I still don't think they will be responsible for chewing needles. Photos (if you can get one) are always good to get accurate ID on possible pests.

My guess is that these trees are the Yatsubusa cultivar. They routinely produce these clusters of buds so management is more about thinning than candle cutting to increase ramification. I have not reduced mine yet but will probably do so before spring growth. The other option is to prune back into the older needles and get rid of the clusters all together. The new shoots from the needles are better spaced and much easier to build ramification. That can be done any time through to mid spring or early summer.

 

[ACooke]

Might want to at least take these down to two buds in the next months when you feel comfortable doing so. Could even wait until late winter given they don’t extend much. We leave two equal length buds with a tight, roughly 30-40 degree separation. This will give time to decide.

The spots and ringing sure looks like the start of a form of needle cast. Happens frequently, especially on trees rarely pruned and low ventilation.


We have a bug, a sawfly, here that will chomp the needles… so check for caterpillars (sawfly larvae or equivalent, if they are in your area. Also rabbits will nibble conifers like this.

3-4 needles per bundle can happen, especially trees with rapid growth.


Other than candle thinning and general pruning to allow better ventilation, not really. Might want to check around to see is a safe product is sold in your area for needle cast. @Shibui likely would know best. You can PM him if you desire.



Not to worry,

Cheers
DSD sends

Thanks DSD, this is very helpful.
Now that i know it's likely needle cast, I can go about treating it.
It's been crazily wet here, so that makes sense. Hopefully we get a little less rain in the coming weeks. The tree is definitely thick currently but was rightly or wrongly hoping to leave it till, or at least late Autumn (which it is now) to thin it out and address some pre-existing whorls (I only acquired the tree in mid-summer/a few months ago - which is quite hot here in Sydney).

Thanks again, this definitely points me in the right direction.

 

[ACooke]

Yellow/brown rings around pine needles is indicative of Dothostroma AKA needle cast. It's a fungal infection that attacks in wet weather. Previous damage can't be cured but you can prevent more infection by using fungicide through spring (and summer if you are watering the foliage or have a wet summer). Copper based sprays work well.

Not sure about the chomped needles. We don't have the same pests as USA so very little that actually eats pine needles down here. Case moth caterpillars could be using them to build their protective homes. Would not think rabbits would be a problem in Sydney? Can't think what else might eat pine needles.
Centipedes don't normally hang out in bunches and they are carnivores so not interested in your pine needles. Maybe you saw something else but I still don't think they will be responsible for chewing needles. Photos (if you can get one) are always good to get accurate ID on possible pests.

My guess is that these trees are the Yatsubusa cultivar. They routinely produce these clusters of buds so management is more about thinning than candle cutting to increase ramification. I have not reduced mine yet but will probably do so before spring growth. The other option is to prune back into the older needles and get rid of the clusters all together. The new shoots from the needles are better spaced and much easier to build ramification. That can be done any time through to mid spring or early summer.

Thanks Shibui ---- to the rescue as so often is the case. That's very helpful.

I'm not sure if you've seen in the media but we've had two periods over the last short while where it's just rained relentlessly and torrentially for well over a week. Fair to say it's been very very wet; so I guess that probably makes sense with the needle case; and you're correct, it is a Yatabusa (the first two photos, the last is a 'full-sized' cultivar and minimally dense) and is overly dense which i was hoping to leave til our cooler months/spring to address and thin (I only acquired the tree mid summer). I might got through and at the very least, remove some prior years needles for now.

There's a few pre-existing whorls which are a bit of an eye-sore that I wanted to address too - hopefully i can nibble them away a little - and thought that'd be best when sap-flow was lower; was planning on doing a lot of it at once - which it seems will be fine to do soon with our cooler weather.

Re. Rabbits - yep they're a rare thing around here and they wouldn't be an issue. I had a decent look yesterday and couldn't see any pests on the foliage. There were no centipedes in the tree's and were solely in the soil - I guessed they might be after another pest present rather than doing any harm themselves.

The only other insect i've seen present was a small Phasmid but I wouldn't have thought they'd favour a pine needle over some deciduous species, as well as eucs nearby.

I wonder if a systemic pesticide would be worthwhile using if i'm unable to visually see anything.

 

[Shibui]

You guys seem to have commandeered the rain we should be having at this time of year. It's so unusually dry down here the trees have taken to following dogs around hoping for some respite.

The Dothostroma has probably been present most of the summer. It takes some time for symptoms to appear which is why preventative spraying is important. I had some here for the first time the summer before last but after a couple of copper sprays there's no sign this year.
I'd probably give them a spray soon though that's probably to late to be effective. Start regular copper spray in mid spring and continue regular treatment whenever you get rains or when the foliage is wet for more than a couple of days at a time.

I would not worry about a few missing needles. It may have been a once off vagrant visitor but I would use a pesticide if the damage continues.

 

[ACooke]

You guys seem to have commandeered the rain we should be having at this time of year. It's so unusually dry down here the trees have taken to following dogs around hoping for some respite.

The Dothostroma has probably been present most of the summer. It takes some time for symptoms to appear which is why preventative spraying is important. I had some here for the first time the summer before last but after a couple of copper sprays there's no sign this year.
I'd probably give them a spray soon though that's probably to late to be effective. Start regular copper spray in mid spring and continue regular treatment whenever you get rains or when the foliage is wet for more than a couple of days at a time.

I would not worry about a few missing needles. It may have been a once off vagrant visitor but I would use a pesticide if the damage continues.

haha; I'm sure most of Sydney would have been happy to have shared our rainfall with you, if we had the chance; it's seemingly been relentless.

I'll start spraying today and do so preventatively in future. The 'aesthetic' effects don't concern me, being in early development but the knock to the health and strength of the tree certainly does; so I'll get on to it pronto.

Thanks again Shibui