Pine Problem

Any suggestions as to what might be causing this "zebra" effect on a Scots Pine belonging to my bonsai friend and fellow IBCer Peter Thorne?

It is something that has just happened this year. Only other snippet of information which may be relevant is that it had a woolly aphid infestation earlier in the year which he got rid of by soaking the tree with soapy water.

A classic case of needle cast Fiona. Get your Copper Fungicide out and start a treatment. Once a month should do it. Three or four applications. I have discovered no needle cast on my Pines this year. I have stopped watering the foliage this last year. May be a coincidence.

Any other possible causes you can think of apart from watering the foliage?

As far as I know, needle cast is an airborn Fungus and ( wild stab in the dark) is going to be worse in a damp environment. I have also fed my Pines very strongly this Spring which may also help. Another factor is the lack of rain down here. As scientific experiments go, I have a lot to learn!!
Don't know if bugs can spread the disease? They will weaken the tree and this could be a factor.

Will thanks for the advice. I have been feeding the tree well and it has been thriving with lots of new growth, strong candles and some back budding. Pines normally grow well in Scotland, and as an indigenous species seem to cope with our wet climate. I have several pines in my collection and most of the others were also affected by the woolly aphid problem, however this is the only one with the pine needle cast. Should I use the Copper fungicide as a routine preventative to be applied to all my pines? If so, can you suggest a particular brand and what strength to use.

I presume the needles with the problem will soon die, so should I cut them off now? Are there likely to be any other effects?

Any further advice would be welcome.

Hello Peter. This disease can be fatal and early diagnosis is the key. I have lost 2 of my pines and no longer leave it to chance. I use Copper fungicide as instructed on the box. I no longer water the canopy either as I think this may promote damp conditions for infection. I use Murphy's Copper fungicide.

All the suggestions to treat needle cast are good. If you can locate any ZINEB it is more effective than copper in the treatment of this airborne problem. Forestry seedling beds of Scots pine planted in glades where moist air can be trapped, are often badly hit.

You are quite right about keeping the needles dry. Pull off affected needles and burn 'em - clean soil of any old dsicolored needles too. Feed your tree well - never mind getting long needles - a vigorous pine can fight off the disease, but it will return, so keep spraying. You need to spray your other pines too. Jap white/5 needle pine, Jap red pine and Jap cork bark pine are all weak in their resistance to needle cast.

The trick is to spray your pines all the time temperatures in any part of the day are 50 degrees F or more. If you spray regularly and clean off spotty needles you can avoid the complaint getting on current or new growth. Once you interrupt the cycle, you're ahead.

Good luck to you. Peter Adams

Hello Peter. Thankyou for confirming my suspicions. I have never been very scientific.......More observant and speculative.

There are about 40 different species of Needle Cast fungi so it really refers to the disease effects from the infection. There is more or less a type of fungus for each species of pine. Below are some of the main species each of which has its own effects.

Bifusella linearis (Peck) Hohn.
Elytroderma deformans (weir) Darker
Lophodermella arcuata (Darker) Darker
Lophodermella concolor
(Dearn.) Darker Lophodermium spp.
Mycosphaerella pini
Rost. in Munk [Scirrhia pini Funk & Parker]
Anamorph =Dothistroma septospora (Dorog.) Morelet

Needle cast diseases are typically controlled in commercial growing by chlorothalonil (Daconil, Bravo, etc). Bayleton (triadimefon), Cleary's 3336 (thiophanate methyl), and Banner Maxx (propiconazole) are also labeled for control. You can also use Copper fungicide as a seasonal pre treatment although it is a preventitive but can break the cycle when coupled with diligent removal of affected needles. If the needles appear to break and bend over at a brown spot, this is the fungus fruiting and discharging spores.

Draconil is used extensively as a fungicide on golf courses and although it is toxic to acquatic life it is harmless to birds. Draconil is recommended for use in Spring before growth fully extends and in Autumn as a preventative for the following season.

Copper based fungicide (bordeux mixture) which is traditionally used for fruiting plants, is typically applied in early spring twice as a wash with a two week interval. It is generally used at concentrations between 4 and 6g per litre. You should note that It leaves a greyish film which remains on the foliage until it washes off some weeks after application.

The problem with pines is that all needle problems give the same symptoms: bands on needles. If you had experienced a bad ozone event in the spring, all the needles would have a band that marked that time period. If you used a phytotoxic chemical for the aphid attack, all the needles could show a band where the young tissue was exposed to that chemical.

Needle-cast fungi are a variable bunch of species, some of which are very minor problem needling no attention; others are serious causes of disease. The way to tell if a pine has a needle cast is to take some needles, put them in a glass jar with some moist toweling, close the jar, and wait to see if fruiting bodies appear on the needles. Then you identify which needle cast is is and act accordingly. At any rate, that's what I do, and that's what a county Extension Agent would do.

I'm not willing to have an opinion on what caused those bands based on that photo.

I was researching this problem myself over the weekend and came across this thread whist searching for needle cast on the IBC. I thought I would mention the use of Vitax Bordeaux Mixture as a treatment. Murphy's Copper Based Fungicide is like Hen's teeth to find and is being removed from the market in 2013. the Vitax product may be the only alternative other than old stock of the strong but now banned products. I have osted about this on my blog if it's of any use to anyone here. MYBLOG - NEEDLE CAST

Fiona/Peter, Id also be interested to hear how that pine has progressed with treatment since the initial post. Is there anything different that has been tried?

Ian, like you I had great difficulty on tracking down the Murphy’s copper fungicide. Whilst I was looking for it, I did cut off the infected needles, but by the time I managed to get hold of the Murphy’s we were past the growing season. However there was no re-infection and no other apparent effect on the tree. As I understood that the right time to apply it was when the tree was growing vigorously I decided to wait until this spring before applying the treatment.

This spring the tree has been growing fine, and I decided not to treat it in case I got the dosage wrong or there was some adverse effect. I know about the maxim that prevention is better than cure, but preventative treatment of pines is not something that is done by other members of my local club, all of whom have several pines, and so I decided to stick with my cautious approach. Thus fare there is no sign of any problem ! By coincidence I was working on this particular tree this evening and so I thought you may be interested in seeing the whole tree. Its still a work in progress but then so is most of this hobby………

Thanks for getting back on this Peter, you're a star :-) Tree's looking great.
How many times did you treat the tree in total, or was it only the once?
If it was going to make a reappearance you would think it would have happened by now.
Luckily my trees are OK, but my friend has 4 Scotties looking pretty sorry for themselves. However, this years candles are strong and extending well. Fingers crossed.

I have found Bordeaux mix to be very effective even on badly affective trees.
Its easy to use, it comes as a powder, add water and spray.

Regards Chris

Bordeaux mix is an amazing thing- one of the first fungicides. It was first used in the 1800's to spray on grapes near roadways in order to keep people from eating them, then a botanist noticed that the sprayed grapes had less disease, and Voila! However, Bordeaux mixture should not be used in very cold or very hot weather or plants may become damaged.