FWIW, needlecast diseases like Rhizoshaera can indeed be successfully treated with the old-school fungicide Bordeaux mix. I've done this very thing on afflicted Colorado spruce, to good effect. And when I say good effect, I mean that this treatment was applied somewhere in the early 1990s, and the trees are still in good shape today.

Bordeaux mix is not such bad stuff to work with-not a lot of potential for off-target harm with this stuff, nor is it dangerous to the applicator. It's really just a means to get the copper molecule in place to disable the fungus. If it is used again and again in the same spot, copper toxicity can develop. This absolutely will not happen with a one-time app.

Then too, I'm not seeing the trees. It is at least possible they're too far gone. I agree with the assessment that drought is the beginning precursor to this disease in spruce, and that subsequent high-moisture atmospheric conditions can deal the death blow later, after the trees are already in this weakened state. But again, I've seen what amounts to complete turnaround with the Bordeaux.

Norway spruce is much more well adapted to typical eastern half of US conditions-occasional drought, frequent wet wether, wet atmosphere, etc. I agree they can get a little bit of the needlecast, but nowhere near what the Coloradys get. I personally have a strong preference for Norway spruce, wherever a large spruce is desired. Good luck!

+oM

Thank you, folks.
Tom, that sound promising. Where do I get that Bordeaux mix and how would I spray up in the high reaches of the tree? I did an Amazon search for Bordeaux fungicide and got a lot of copper fungicide results...maybe they are pretty much the same? They don't seem crazy expensive.

I think I could definitely use it on my smaller spruces, which by the way...Ken, the Montgomery already shows signs of it and I had to limb it up the other day to get the bad stuff out of there.

Does anyone have a thought as to whether using my gray water under the spruce could be helpful vs. harmful? So far, we've had a lot of rain this year, so not sure if it's needed. However, since Tom mentioned that drought followed by moist years info...don't want to make it TOO wet, right?

I will consider taking it down, Ken. Might be in the perfect spot for my Beech!

Here is a link that might be useful: Copper Fungicides

when the guy sprayed the neighbors trees.. he had what looked.. from a few hundred feet away [i wasnt getting any closer] .. like a 1.5 to 2 inch fire hose ... and he was spraying this stuff up into the 40 foot tall tree ..

can you really see doing this on your 3 story tall tree???

if you do ... have them add an insecticide.. and be done with mosquitoes ... lol ...

there is always a gap.. between what is possible.. and what is reasonable ...

i have no objection on you doing it SAFELY ... on smaller trees ..

ken

Ken brings up a good point-practicality of spraying large trees. I had it easy in that we, the municipality I work for, have bucket trucks. That's what we did, just went up with handsprayers up in the bucket. I f not for that, you'd need some kind of mighty spraying equipment. These things are less common nowadays, but there used to be mist blowers and other assorted high-power spray rigs. I guess it's for good reason that such rigs are less commonly used nowadays-spraying copper-baswed fungicide is one thing, but of course these rigs were used to spray DDT and a host of other dangerous and persistent chemicals back in the day.

Yes, Bordeaux mixture is copper sulfate and quick lime, so a relatively simple affair. I'd look at your more complete garden centers, farmer co-ops, what have you. Not going to be at the hardware store, I wouldn't think. And of course, don't neglect to remove already-infected plant parts, They are a source of inoculum for new infection. I think you said that you do/did that already, but just saying...

+oM

As long as your gray water doesn't contain any harmful chemicals it should be fine. I think it's much easier to over water blue spruce, then it is to underwater them. They like blazing hot sun and do not like wet feet, just a quick drink, with fast drainage. Another thing with needle cast is trying to avoid the needles getting wet when you water, always apply water to the base of the tree, preferable in a slow drip format.

The bigger spruces are not worth trying to manage. Like Ken said, I have seen large spruces being sprayed with firehose-like sprayers, but it just isn't worth it. Spruces don't really ever fill out again either, so most just opt to limb them up and eventually replace.

Many have had great success with smaller dwarf varieties of blue spruce using copper fungicide and/or any spray that contains Chlorothalonil. I have used DACONIL on 2 of my blue spruces and will see how they do, so far no negative affects and blue wax was not impacted. I believe that would only be bothered if you sprayed oils, which you never want to do to a blue spruce.

If I had to spray them forever I wouldn't do it. But this is a 1 or 2 season ordeal. You need to get this fungus under control or it will spread to your other blue and possible white spruces. Make sure you spray when the buds are 1/2 way out and again in 3-4 weeks. You should do this for at least 2 years in a row and maybe 3...To me, this is manageable and worth it to save a couple of smaller specimens I have. I have also heard it's good to switch chemicals from year to year to ensure the fungus doesn't develop an immunity to one chemicals... don't know how much truth there is to this though.

Good luck. I will be sure to provide updates on my trees next year and after.

Yeah, the trees we sprayed weren't full-grown yet, maybe more like thirty-footers, if that. I too would not opt to spray full-grown Colorado spruce. What I have found gratifying about this single case is that those trees went from being things that many wanted to get rid of to a grove that actually seems better than most I see. And yeah, Daconil is another option.

Chemical resistance among rapidly-replicating pest species is a real thing. And the key things to do are to actually not skip around to different chemistries but to use one until it becomes clear that a resistant population has arisen, then move to another chemistry. The way these things can mutate, it can get to be a moving target sometimes. I have no idea if any resistance of the fungus responsible for this and and those responsible for other needle blights has been documented though.

+oM

Thanks everyone, I have decided to call around for prices to get the tree removed. After thinking about paying someone to spray it, I think the best thing is just to say goodbye. Plus, my Norways are showing quite a bit of

Tom...are you from Appleton? If you know of anyone that does a good job for a fair price, I'd love to know...

One more question...what do I do with this brush? I assume it cannot be chipped up and that it should not be laying around (I have a lot of room for stuff to "lay around" in the back, but am thinking it needs to be removed?

Thanks! Mary

+oM, good info on chemical resistance. I will be sure to stick with one chemical, unless resistance shows up.

Mary, it is recommended that infected brush be burned or removed.

Good to hear you found resolution by removing the tree(s). Spraying fungicides on 3 and 4 story trees cannot usually be done without significant drift. Not sure about the location of the trees in this specific instance, but in many states, drifting pesticide onto your neighbor's property is illegal.

A big problem today are applicators who are trying to control needlecast via spraying fungicides on spruces that were planted as privacy fences These privacy line spruces are commonly planted too close together which promotes fungal growth, and they're often planted along the property lines. When you start to look, you see them throughout neighborhoods, and unfortunately too many applicators will willingly accept an expensive spraying contract without regard to spraying down the neighboring playset.