New needles are green (circled in red), and older needles are yellow (circled in blue) on this spruce. Spruce needles that are yellow with no visible fruiting bodies on the needles may be suffering from nutrient deficiency due to constant wet soils this year, or they may have a fungal disease called SNEED (spruce needle drop). Photo by Linda Williams, WI DNR.
In late summer and early fall I had a few calls about younger spruce with yellow needles. These trees were typically 8-20 years old and were a very yellow color, with new foliage emerging a green color but quickly fading to yellow. There are two things that came to mind this year. The first thought is that we’ve had a very wet year. All year long roots were often in saturated or very moist soil. Consequently. the yellowing could be a sign of nutrient deficiency, specifically nitrogen, due to the saturated soils. The second possibility is a disease called SNEED (an abbreviation for ‘spruce needle drop’), which I typically see on heavier soils.
SNEED in spruce is thought to be caused by the fungus Setomalonomma holmii. Pathogenicity of the fungus has not been proven, but it is the primary fungus present on trees with a particular suite of symptoms. Spruce with SNEED have current year needles that are a nice green color, but older needles will be yellow or yellow/green in color. Black fruiting bodies will look like pepper sprinkled generously on the twigs of the affected branches. Old needles, although not showing any fruiting bodies, will drop from the tree prematurely, and repeated years of this will cause the tree to thin, decline, and can lead to mortality. I’ve seen this primarily in plantations of white spruce on heavy soils, but have also seen it in blue spruce plantations; it’s reported in Norway spruce as well. I don’t know of any sure-fire chemical options to prevent infection or to help the trees recover. Management typically involves removing the most affected trees in the plantation, minimizing stress, and minimizing standing water or waterlogged soils where possible.
Written by: Linda Williams, forest health specialist, Woodruff. Linda.Williams@wisconsin.gov; 715-356-5211, x232.
The first of three sessions was held for Wisconsin’s Community Tree Management Institute (CTMI). Twenty-six students from across the state met in Green Lake, WI October 17-18. These municipal tree managers (who lack technical and program management in arboriculture) learned the foundations of urban forestry. Through hands-on training and exercises, students learned about: canopy and measurement tools, tree benefits, awareness and support, politics and policy, leadership, partnerships, legal issues, ordinances, budgeting, tree boards and utilities. Instructors for session I included: municipal foresters, public works directors, a UW Extension agent, utility representatives, consultants and DNR staff. The variety of instructors, their perspectives and interactive components is meant to appeal to all learning styles. 
The Urban Forestry Council held their most recent quarterly meeting on October 13 at The Oxbow Hotel in Eau Claire. This was the second time the Wisconsin Council met with their colleagues in Minnesota, board members from the Minnesota Shade Tree Advisory Committee and MN DNR urban forestry staff. In addition, they were joined by Urban Forestry Council members from several additional states: Indiana, Iowa, and Michigan. The Wisconsin Urban Forestry Council and Wisconsin DNR were pleased to welcome these urban forestry representatives from the region for the meeting.