Help! Blue Spruce fungus, or insects?

[sftong]

Hello Helpers,

I live in central Ohio. I have a 8 feet blue spruce which has suffered from major lost of needles / leaf. It started in summer 2016, where I sort of neglected it during the summer and did not water it enough. So I thought the lost of needles were due to the drought and stress. The leaves actually turn brown and black.

This year summer, however, was blessed with much water. I also tried to water the plant once a week for total 3 minutes. But recently many needles still turn brownish and black again. Other blue spruce next to it never experience such fate.

Please refer to the pictures below. I appreciate any advice given, as well as treatment ideas. FYI, I did not see any insect or their nests around the tree.

Thanks
Sean

 

[Jason Douglas]

Looks like needlecast.

I'm in Cbus too.

 

[JeffGu]

Indeed. Are the stomata (rows of little, white dots on the underside of the needles) black? All of them, or scattered? That would be a pretty good indication of Rhizosphaera or Stigmina fungus that causes needlecast disease in spruce. They affect different species of spruce, and I have no recollection of which one affects which species, but they can be treated with a fungicide as long as you do it at the right time of year. Jason might know about that, his memory is still relatively intact. Well, when he's sober, anyway. I'm never sob.... er... I mean, my memory is not so good.

It's rare around here, but we've had buckets of unseasonable rain and I've seen a bit of it. Up there, it's probably a lot more common during these wet years.

Jason is right, though... that certainly is what it looks like. There's some other things that can cause similar browning/loss of the older needles, but that purplish color sure looks like needlecast. You can't just spray fungicide on it any old time of the year, though. You'll just waste a bunch of fungicide, and might do more harm than good.

 

[ATH]

Looks like there may also be some Spruce Spider Mites (SSM) damaging that as well. The way the inner needles are a little off color, but not purplish and they way they are laying flat is typical of SSM damage. that is a cool season mite, so they wouldn't be active now. They can be effectively treated in the spring or fall.

The fungicide for needlecast goes on later in the spring - when needles are about 1/2 length and needs to be repeated for 2-3 times per year for 3 years.

While there is likely no treatment to do now, it is not a bad idea to get somebody out who knows what they are doing and plan next steps. (I don't know him...but if Jason is in your part of town I kinda get the impression he would be a good call...)

 

[BC WetCoast]

The other possible pest could be spruce aphid, but not knowing your area i dont know if it is there.

However, it is possible for drought stress to show up 2 to 3 seasons after the event.

Also watering for 3 minutes is barely enough for water to reach grass roots, let alone tree roots.

 

[Jason Douglas]

Sober...not at the moment. Good points made all around.

I generally dont recommend blues be planted around here because of the needlecast pressure and likelyhood of canker and/or root rot developing later on. Dreadful plants here more often than not.

 

[sftong]

Thank you Jason, Jeff and ATH for the information.

After almost 2 months, I have possibly some new information to share. Please see the first 3 pictures below of the Blue Spruce, where there is white resin around the trunk and branches. I touched it, and it is sticky.

Is this Canker? If so, any thoughts of treatment?

I try spraying Baking Soda 1 month back when it was still hot around 80+ F. Doubt that helps with Needlecast or Canker, so far.

Appreciate any feedback. FYI, I live in Columbus OH

 

[sftong]

Additional new images

 

[ATH]

Looks like it could very well be Cytospora..that is a tough one to deal with. Message Jason to see if you can get him out...he is in Columbus. I am in NW Ohio...or I'd offer to come have a look.

 

[Jason Douglas]

2nd on cankering. Phosphite fungicides can delay the inevitable but I wouldn't recommend treatment. Remove and replace