Often, this occurs in pockets or areas in a field and usually affects only 1 to 5 percent of the trees (Photo 6). By early spring, the spots are larger and more obvious, eventually turning the pine needle yellow. You will need to determine what the cause is before taking any action. Black spruce is hardy in USDA zones 3 through 6. Unfortunately, there is little that can be done to alleviate problems from poor planting or a poor site. Spruce does best with full sun, acidic soil and adequate water. We occasionally receive spruce samples in the Plant Disease Clinic that show yellowing of the needles, sometimes only older needles and sometimes both older and younger needles. Such stresses include problems with the site, such as too wet or too dry a site, or excessively compacted soil. Such stresses include problems with the site, such as too wet or too dry a site, or excessively compacted soil. An overall yellow appearance on spruce may also be caused by spider mites. Spruce spider mites This mite primarily feeds on older, inner needles, causing needles to look pale, yellow and sickly. You will need to determine what the cause is before taking any action. White spruce is somewhat susceptible. Norway spruce is relatively resistant. The row of smaller spruce is also yellowing. When Should I Spray Conifers for Needle Diseases. Brown needles have tiny, black fungal fruiting structures in rows on either side of the midvein on the underside of the needle. Yellowing of spruce may be caused by a variety of noninfectious stresses, particularly problems with the roots. Applying fungicides, insecticides, or fertilizer is unlikely to help the situation. Problems with planting are also a common culprit. Stigmina needle blight: Year-old needles turn yellow, brown … In subsequent years, the needles stay attached but turn purple to gray. Asked April 10, 2015, 11:48 AM EDT . It does not look good. Yellowing of the needles can be a symptoms of several problems including; transplant shock, wet feet, too dry, poor weed control, insects, etc. Norway spruce brown needles. Ames, IA 50011-2031 1 Response. The mites themselves may be green, pinkish or brownish-black and are tiny; the adults are only about 1/60th of an inch long. Needles may desiccate during extended dry or hot periods in late August and September, turn yellowish-tan yet remain on trees until fall, then come off during harvest and handling. Yellow needles, typically on the lower branches, in mid-to-late summer. Norway spruce (Picea abies) twig and cone Pegs obvious where needles have dropped off Spruce identification Needles are short, stiff, and sharp. Large bare areas develop on the tree as needles fall while the new, current year's needles appear healthy. You can either send me a photo or send a sample to MSU Diagnostic Services (www.pestid.msu.edu) to determine what may be going on. Sawfly damage is seen from about mid-May through July. Yellowing of spruce may be caused by a variety of noninfectious stresses, particularly problems with the roots. Pines, spruce, firs and even arborvitae will drop needles in the fall. Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Horticulture and Home Pest News, and Iowa State University Extension and Outreach. Ask an Expert is made up of groups and individual experts. by Christine Engelbrecht, Plant Pathology Like us at Plant and Insect Diagnostic Clinic, Like us at Department of Plant Pathology and Microbiology. (800) 262-3804, Iowa State University | PoliciesState & National Extension Partners. Problems with planting are also a common culprit. 3 Responses. Ingham County Michigan. You can either send me a photo or send a sample to MSU Diagnostic Services (www.pestid.msu.edu) to determine what may be going on. Copyright © 2020ISU Extension and Outreach I had planted 100 Norway spruce this spring (April 2015), I've noticed beginning in October that all the needles on about half of my trees have turned yellow. Some locations have an additional infection period in September and October. The large one has yellow and brown needles along the inner half of each branch all the way up the tree. Stigmina needle blight: Year-old needles turn yellow, brown and then fall in the Spring a year after infection. These problems emphasize the importance of starting with an appropriate site for a tree, and planting the tree properly. Such damage typically appears as yellow speckles on the needles when viewed under magnification. Such symptoms are rarely a result of infectious disease. Often starts at the bottom of the tree, on the inside, and works its way up the tree Fungal spores are spread by the wind and infect pine needles during moist weather from August to October. Yellowing of the needles can be a symptoms of several problems including; transplant shock, wet feet, too dry, poor weed control, insects, etc. Norway spruce is relatively resistant. Yellowheaded spruce sawfly and spruce budworm feed on new foliage on white, blue and black (Picea mariana) spruce trees. Brown needles beginning to fall, leaving large bare spots on trees that next summer or fall. They produce fine webbing, especially at the base of the needles. Will the trees make it? If the Norway spruce has yellowed needles, it's due to lack of sunlight and poor nutrition. Pine needles then turn brown and shed through the summer, with only small patches of green current-season needles left by late summer. The following year, the infected needles develop a black line on them.