Possible Mite Damage?

[Reach]

So I am far from an expert on insect damage, especially on conifers. I’m thinking this looks like mite damage, but I would like a second (third, fourth, fifth...) opinion as to what this is for sure.

 

[ghostice]

Last few years, we have been seeing lot of sick spruce - both black spruce and white spruce (i.e. not Colorado Blues). Some have what looks like a combination of Cytospora, needle cast(s) (Weirs) and late in the summer here, spider mites (there is also something they are calling SNEED which looks a lot like spider mites apparently). Our spider mite infestations are really hard to control, if you can at all - timing of miticide is critical and using a pesticide often just kills off natural predators and the mites come back with a vengence later. Even with control, I've found that the spruce end up looking like they've had the juice sucked out of them - large areas of only vertically downwards limply hanging branches - still green - (see pics) rather than their normal "perky" appearance.
There's lots of miticides (web search) and here's some controls listed for needcast diseases:

Agriculture | Province of Manitoba

Province of Manitoba

www.gov.mb.ca

If anyone has brilliant ideas I'd like to hear them too please.

 

[JD3000]

Pics are far away but are you sure that's not typical secondary and tertiary branch weeping typical of Norway spruce?

 

[JD3000]

So I am far from an expert on insect damage, especially on conifers. I’m thinking this looks like mite damage, but I would like a second (third, fourth, fifth...) opinion as to what this is for sure. View attachment 58991

Not mite damage though there may be some subtle mite damage amongst all that nastiness

 

[ghostice]

Pics are far away but are you sure that's not typical secondary and tertiary branch weeping typical of Norway spruce?

No I don't think so - there's areas where all the trees are about the same age and same planting style and soils etc. yet they're turning out like this. The specimens that do exhibit this weeping have had spider mites for two summers, at end of summer usually. Can't spray the whole neighbourhood though, over and over . . . . (also are black spruces and white spruces, nothing more exotic). But my own theory is it's a combination of things. Sad to watch these trees decline little by little, in spite of care.

 

[JD3000]

Bummer.

 

[ATH]

Let's start with the first pic...that is a fir, not a spruce. (Douglas-fir?) Could still be spruce spider mites...on that species, but not those pics.

Rhabdocline Needle cast??? (We don't have a lot of Doug-fir here, so I'm not as strong with these...)

 

[Reach]

Let's start with the first pic...that is a fir, not a spruce. (Douglas-fir?) Could still be spruce spider mites...on that species, but not those pics.

Rhabdocline Needle cast??? (We don't have a lot of Doug-fir here, so I'm not as strong with these...)

I believe that it is a Douglas Fir. There are several Blue Spruce on the property and none show signs of Spruce Spider Mite. This tree does not look right for that to me either, as it is a pest I am familiar with. My thought is that the needles look like mite or scale damage, but the needles are consistent across the whole tree.

If it makes a difference, we have had an exorbitant amount of rain over the past year, and this tree has been in a pretty wet area for much of that time due to the lay of the lawn where it is.

 

[ghostice]

Found this on the web today (lots of pics) which might be useful to someone:

https://www.fs.usda.gov/naspf/sites/default/files/publications/christmas-tree-pest-manual-3rd-editionlowres.pdf

 

[ATH]

That's a good book for the common evergreen pests. Not comprehensive, but very good for what it has. Worth buying the hard copy...

 

[jed1124]

Are the trees planted near a roadside? Looks like salt damage. Mite damage will present as stippling on the needles and they are often chlorotic.

 

[Reach]

This tree is a couple hundred feet from the nearest road, the only possible chemical contributor is pool water. There is a swimming pool nearby that was drained at one point last summer and refilled, but that was probably nine or 10 months ago. Since then, we have had nearly double the annual average rainfall for our area, which I would think should wash away any residual chlorine.

 

[ATH]

Could be problems with saturated soil??? Doesn't necessarily look like that, but that can certainly be a big stressor...between a pool full then above average rain...chemicals certainly wouldn't help!

 

[Reach]

I thought about that, but it doesn’t look right to me. I can’t say for sure though, it might be a combination of chemicals and saturation. It’s very even over the whole tree, so that makes sense as an option. The tree does appear to be budding nicely, so hopefully whatever it is will grow out.

 

[evo]

Just going to drop this here... I see it all the time in small pockets here and there. Some genetics are more susceptible than others.

Nothophaeocryptopus gaeumannii - Wikipedia

en.m.wikipedia.org

Fir, Douglas (Pseudotsuga menziesii)-Needle Cast, Swiss

Cause Nothophaeocryptopus gaeumannii , a fungus found on trees of all age classes from natural forests to ornamental landscapes. This disease is considered one...

pnwhandbooks.org

 

[jed1124]

Swiss Needlecast and Rhabdocline needlecast are a big problem with Dough Fir but this tree is not presenting like either of them.
I like the water/possible chlorine line the op is going down. Phytophthora maybe?

 

[davef]

Phytophthora diseases is found on cranberries in low bogs close to the coast or within the mountains on trees growing many thousand feet on top of water level.

It may just be excess water or from flooding. If this organism will manufacture swimming spores (zoospores). I don't know what level of investigation you want to go but zoospores are drawn to the roots and start the infection.

 

[evo]

Swiss Needlecast and Rhabdocline needlecast are a big problem with Dough Fir but this tree is not presenting like either of them.
I like the water/possible chlorine line the op is going down. Phytophthora maybe?

Same photo. Try again

 

[ATH]

With those black dots, it could be Rhizosphaera needle cast or back to Rhabdocline???

Perhaps send samples to Penn State to see if they can get a positive diagnosis so you can come up with a treatment plan if it is one of those:
https://plantpath.psu.edu/facilities/plant-disease-clinic

 

[jed1124]

Same photo. Try againView attachment 60278

Didn’t see the fruiting bodies. I stand corrected.