Dead leader on serbian spruce

In mid-July I noticed the leading tip of my Serbian Spruce turn brown and lose it's needles- we had a bad hot spell followed by a great deal of rain and so I attributed it to bad weather. Within about 2 weeks, the branch had died back from 6 inches to about 18 inches, so I immediately cut it back to healthy wood. Fortunately when I bought the tree, it had two leaders- I had always meant to cut the weaker one back and now I'm so glad I didn't.

I've read where this tip die-back can be attributed to certain moth larva, but when I inspected the branch, it was covered with these white blotches. The blotches were sticky, but not runny. I'm trying to determine if this is some type of critter or is it a mold/mildew thing. Please see attached photo...I'm trying to determine my next course of action for the new leader.

Many thanks for any and all input,

Patrick

If you still have the dead leader, take more pictures of it and zoom in on the white blotches, etc. This image is low resolution and not clear enough to make out much.

There types of piercing/sucking insects that could infest your tree, as well as other non-insect pathogens.

Tell us more about this tree's life history - when it was planted, what the soils and moisture conditions are like, etc.

You should also post pictures of your whole plant, and the context in which it is growing. This additional information can often lead to ideas about why your plant is having problems, and suggestions for improving this plant's health.

If you still have the dead leader, cut it lengthways, and see if the middle has been hollowed out (or filled with insect droppings). Chief suspect Pissodes strobi.

The white sticky is probably just resin bleeding.

Resin

More pics would be good. But tentatively agree with above comment, the timing of the dead leader coincides with the life cycle of the white pine weevil - which attacks many species other than white pine (notably Norway spruce, Picea abies, locally here) - from experience with eastern white pine, nature will take it's course next year and you may have a few side branches fighting for apical dominance - if you have a pruning pole, prune out each (July), but leaving the best. The weevil's don't travel far so a recurrence is likely.

The tree is about 3 years old and 9 feet tall now in a partially shaded part of the yard. Soil is slightly clay so stays moist, but I wouldn't say wet. Attached is a cross-section of the branch- the length displayed is about 6 inches. Does look like some type of larva was in the middle although it was just mush when I poked it with a toothpick. Would you suggest spraying the tree as a proactive measure or just stick with pruning?

Again, thanks everyone for your input and advice.

Patrick

Yep, that's been bored out.

Resin