Our observant readers probably noticed something unusual in the photo accompanying the last post. As is my custom after the first mowing, I included a photo of our yard that showed an empty spot where we used to have a spruce tree. I had to make the painful decision recently to remove that tree, and I hope my experience can help someone else avoid the loss we've endured.
About a year ago I noticed some brown spots on a few branches of the tree, but since they were high in the crown and limited in number I didn't give them much thought. The brown sections grew in size and number over the next few weeks, prompting me to investigate more closely. Although the image below was taken this spring, the general appearance of the tree approximates what I observed early last summer.
A little online research identified the pests as a bagworm that feeds on both evergreens and deciduous trees, but since spruce trees don't regenerate their needles, the damage to conifers is more noticeable than when these pests attack deciduous trees. My only consolation was the fact that the worms finished stripping branches by mid summer. The males emerge from the cocoons in a few weeks as a moth to fertilize the females that remain in their cocoons, and the fertilized eggs remain in the cocoon until late spring the next year.
I vaguely recall seeing a few cocoons on this tree in 2013, but they didn't excite enough curiosity in me to cause me to investigate. Now that I recognize bagworm cocoons, I won't delay in acting in the future. Hopefully others will learn from my experience and will save their trees before it's too late.