Master Gardener: Evergreen Bagworms are hiding in plain sight Joy Ceraldi Last fall my husband and I had some trees planted in our yard. We live in a rural area and have some established evergreens. The man who was planting the new trees happened to notice something on our Colorado Blue Spruce trees. Near the ends of many branches were woody-looking clusters that, to me, looked like they were a natural part of the trees. Our tree expert explained these were not parts of our trees, but parasitic evergreen bagworms. He instructed us to remove the clusters and burn them, which we did.