Spruce tree bleeding extensively

Asked September 11, 2019, 8:04 PM EDT

We have one particularly large and healthy-looking Spruce tree on our property that towers over everything. In just the last few days, we noticed an alarming amount of sap dripping from all over it's trunk. Truly massive amounts, more than I think I've ever seen - the sap seems to be coming mostly from small holes drilled through the bark, either from sap-suckers or beetles, we're not sure. It really feels like it happened all-of-the-sudden, we definitely don't remember seeing holes and pitch like this before in the year+ we've lived beside the tree. Here's some pertinent info that might help: There are thousands of holes, all told, all the way up as high as you can see into the tree's canopy. Occasionally there seems to be a bit of order to the holes, but largely, it doesn't seem so linear and organized as a sapsucker's. I haven't noticed chaff or beetles themselves, but I've heard they often go unseen. The holes are all about the size of #2 pencil, many are slightly ovular, and only slightly bigger. We haven't seen any needle die-off or other signs of bad health in the tree before or now, but it seems to have just started all of the sudden, so I'd expect to see health effects develop over a course of time. There's one other thing that may or may not be connected: We've seen a bunch of holes of about the same size in the soil around the tree's root bed. They're not organized, and could very easily just be something unaffiliated to this tree and that we've just never noticed before, but both my wife and I noticed it for the first time in the same general time period. I've attached pictures. If there's more I can do to aid identification, let me know. Thanks for you help!

Tillamook County Oregon

3 Responses

Thank you for the detailed description and photos of your tree. I am sorry to hear that this is happening. From the pictures and your description of the holes, I would agree that this is not a sapsucker, since they typically leave a more uniform pattern, and "peck" only as deep as their beaks can reach.

Unfortunately, this looks like a combination of spruce beetle and flatheaded borer infestation. I spoke with Dr. Christine Buhl, Forest Entomologist for Oregon Department of Forestry Forest Health, who confirmed this diagnosis based on the extensive pitching (spruce beetle) and size and "D"-shape of the larger, "pencil-sized" exit holes (flatheaded borer). For more information on the spruce beetle for a description of this insect pest, visit https://csfs.colostate.edu/forest-management/common-forest-insects-diseases/spruce-bark-beetle/. The content is universal for the insect, although it is tailored to Colorado where it is a bigger issue. Here is a link to the quick guide that can also be downloaded form the above website: Spruce Beetle – 2014 Quick Guide (493 KB PDF).

The good news is that you mentioned that your tree's canopy is still green, and apparently still doing OK. The extensive pitching is a sign that your tree is currently able to use its defense mechanisms to attempt to counter the attack by pitching out the spruce beetles. More resilient trees are sometimes able to sustain attack from this beetle, so not all hope is lost for now.

You will want to keep an eye on your tree and monitor its progression. Since the beetles go dormant in winter, the canopy will most likely remain green through the winter. If colonization is successful, your tree may start to fade in the spring. There are registered chemicals available that can prevent future attack, if this is an approach you are interested in pursuing. Timing is key for the application of this chemical, so if you proceed with this option, it will need to occur before the beetles emerge and fly in the early spring. It is recommended that preventive sprays be applied only by a certified applicator.

Regarding the flatheaded borers, these are secondary insects that typically follow an initial attack by the spruce beetle. Unlike the spruce beetle that "etches" the cambium of the tree, flatheaded borers actually bore into the wood to feed and reproduce. Extensive colonization can further weaken and compromise your tree.

For both the spruce beetle and flatheaded borer, you will notice some bird activity on your tree, as they are searching for juicy beetle larva.

I wish you the best and have hope that your spruce tree can endure.

What about using pheromone traps? The tree is extremely tall and very close to the house and neighbors, and for these reasons, as well as environmental, we're nervous about pesticides. For a very large tree like this, would you recommend pheromone traps strategically placed at the right time to help defend against a hatch?

Hi again:
I totally understand why you would feel nervous about using pesticides on your tree. Synthetic pheromones are available for spruce beetle, but for monitoring purposes only, not population control, at least for an individual tree that is already under attack. Also, flatheaded borers do not respond to these chemicals.

If your tree continues to decline and due to its proximity to yours and your neighbor's house, removal may be the only option. I wish I had better news to share.