Colorado spruce (Picea pungens), often referred to as "blue spruce", is a widely-planted tree in Iowa but suffers from some serious disease and environmental stress issues. Diseases like Rhisosphaera needle cast, Stigmina needle cast, and Cytospora canker are common and often cause extensive damage including needle drop, branch die-back, and death. Trees do not grow well in Iowa's heavy, often wet, organic soils, and this Rocky Mountain native does not appreciate Iowa's hot, humid summers. These less-than-ideal growing conditions for this species put trees under stress making them even more susceptible to disease and insect pest issues. Finally, the mature size of these trees is too large for most residential settings.
For all of these reasons, Colorado spruce is not always a good tree selection for Iowa.
There are several other species of conifer that can be used instead of this species in landscapes or windbreaks. Consider planting these trees instead of Colorado spruce.
Alternatives to Colorado Spruce
- concolor fir (Abies concolor)*
- eastern white pine (Pinus strobus)+
- Norway spruce, (Picea abies)
- baldcypress (Taxodium distichum)*
- Korean pine (Pinus koraiensis)
- Serbian spruce (Picea omorika)
- Korean fir (Abies koreana)
- European larch (Larix decidua)
- dawn redwood (Metasequoia glyptostroboides)
- eastern hemlock (Tsuga canadensis)*
- Douglas fir (Pseudotsuga menziesii)*
- Alaska cypress (Callitropsis nootkatensis; syn. Cupressus nootkatensis, Chamaecyparis nootkatensis)*
*Native to North America; +Native to Iowa