Sickly Spuce Trees

Michigan Escapee · Oct 28, 2015

I'm really not sure what exactly is doing these in. Another thread mentioned spruce blight, and from the looks of the closeup on the pretty much dead one, it seems to have some kind of fungal issues. The insects were having a field day on them until they were treated with bayer protect and feed, and that seems to have gotten rid of most of the insects

So, looking like the more or less dead one will have to go next spring. Wondering if there is any harm leaving it up over winter, or if it's all the same as the surviving one seems to have done a complete 180 since this spring.

ATH · Oct 28, 2015

That is Austrian pine.

The second picture is easy: sapsucker.
3rd picture is an old pruning cut with sap flowing around it.
You didn't post any pictures of heavy sap flow that would indicate Zimmerman pine moth which is very common cause of demise of Austrian pine.

I'd suspect Pine wood nematode with the way the tree in the 5th picture looks (sudden browning of the whole tree)... That is generally considered a pest of stressed trees. Could also be getting started on the other tree.

Michigan Escapee · Oct 28, 2015

Both of them looked pretty nearly dead about 1 1/2 years ago. A fair amount of fertilizer perked them up a bit, one recovered nicely, the other tried, but didn't really get anywhere. Was able to cut off a good part of the dead sections on the other tree, and will probably get the rest removed in early winter.

Raintree · Oct 29, 2015

When it comes to Austrians the first thing to rule out is diplodia.

ATH · Oct 29, 2015

One shoot in the first picture (top center) looks questionable for Diplodia, but the big one in the center of the picture looks clear...

Michigan Escapee · Oct 29, 2015

I wonder if that tends to affect hedges as well? I see some rusty looking dead spots on some of them, but thought that was due to spider mites, and the plants being generally sickly. After a number of fertilizer dosing, those seemed to recover pretty good. Suppose I could put down some wide spectrum fungicide and see if that does the trick.