brown needles on black hills spruce
Black hills spruce (white spruce) is a hardy, desirable and popular planting with fewer problems. The species however is susceptible to various diseases and insects including needle and stem rusts, needlecasts, cankers, spruce sawfly, spruce budworm, and eastern spruce beetle. Spider mites and bagworms are some of the most common problems, especially on stressed trees. Repeated infestations can do serious injury to the plant. Mites are tiny and one way to determine if present is to hold a white sheet of paper under a branch or branches while shaking the branch, looking for any movement as the mites will be very small.
The first requirement is a correct diagnosis, something we can't do from this vantage point, before considering any treatment. Best way to gain this is with an onsite visit by a Certified Arborist, one who specializes in these matters. Find one or more Certified Arborists in your zip code at www.treesaregood.org Go to the Find an Arborist tab. Arborist evaluations are not expensive and where you can learn exactly what is going on in your tree. There are often treatments available but procrastination loses valuable time in saving spruce from disfigurement that can lead to tree loss. As our climate becomes generally warmer, it’s anticipated that several evergreen species, including white spruce, will become more difficult to grow here.