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Community for Iowa

Introduction —concolor or With their ever-present foliage, white (cone-bearers) make Height: 50 feet Width: 30 feet excellent screens, windbreaks, and Appropriate for most of Iowa hedges and provide year-round Abies fraseri— visual interest. Unfortunately, the Height: 40 feet Width: 25 feet number of conifers recommended Best in northeast Iowa on cool, for Iowa has dwindled in recent moist sites years because several species have proven sensitive to our stressful Juniperus— or have fallen prey to Culture various pests. For example, It is difficult to generalize about (Austrian ) has growth habits of because been severely disfigured by fungal species vary from low-growing pathogens Dothistroma pini and groundcovers to pyramidal trees. Sphaeropsis sapinea, which cause All junipers prefer open, sunny Dothistroma needle blight and locations; in heavy shade they (Sphaeropsis) tip blight. Pine become thin. Junipers do best wilt continues to decimate Pinus White fir in light soil and tolerate many sylvestris (Scotch pine), the result Abies—Fir different pH levels. of infestation by Bursaphelenchus Culture xylophilus (pine nematode). Members of the genus Abies require Recommended Species moist, well-drained, acid soil with Juniperus scopulorum— The following list of recommended high atmospheric moisture and Rocky Mountain juniper conifers is a guideline for cool summer temperatures. Iowa’s Height: 30 feet Width: 10 feet home-owners and landscape hot, dry summers limit the use of Check with local nursery operators professionals. Not every will many Abies. do well in full sun for best selections. work in every situation, but when or light shade but are not suited for planted on appropriate sites and Juniperus virginiana— harsh urban sites. Transplant in the protected from drought, excess eastern redcedar spring using balled-and-burlapped moisture, deicing salt, pesticides, Height: 40 feet Width: 25 feet or container-grown stock. Limit and mechanical damages, these Many are available. pruning to removal of multiple valuable woody should have leaders and broken branches. long, useful lives. Recommended Species Typical mature height and crown —balsam fir spread in feet are listed after each Height: 40 feet Width: 25 feet species (height/spread). Best in northeast Iowa on cool, moist sites

PM 1429g Revised March 2008 Picea— Culture Members of the genus Picea perform best in moderately moist, well-drained soils. Plants will be stressed on hot, dry sites and may succumb to insect and disease attack.

Recommended Species —Norway spruce Height: 80 feet Width: 40 feet Good windbreak tree

Picea glauca—white spruce Height: 50 feet Width: 25 feet Withstands wind, heat, cold, and drought

European larch Picea glauca var. densata— spruce Larix—Larch Height: 40 feet Width: 25 feet Culture Susceptible to drought stress; Larches are deciduous conifers that spruce rather slow-growing prefer moist, well-drained sites with plenty of sun. —Serbian spruce Height: 60 feet Width: 25 feet Recommended Species Protect from desiccating winter Larix decidua—European larch winds Height: 75 feet Width: 50 feet More tolerant of Iowa conditions Picea pungens—Colorado spruce than American larch Height: 40 feet Width: 25 feet Very adaptable Larix laricina—American larch or tamarack Height: 60 feet Width: 30 feet Requires moist soil and cool sites

Serbian spruce Pinus—Pine Culture are more tolerant of poor soils, urban conditions, and adverse exposures than or firs. Because of their mature size, pines are used most effectively on large scale sites, such as Mugo pine parks, cemeteries, golf courses, large commercial properties, and spacious residential lots. Recommended species Pseudotsuga menziesii— Height: 20 feet Width: irregular Douglas fir A picturesque slow-growing, Height: 80 feet Width: 40 feet ornamental pine Culture Pinus bungeana—lacebark pine Prefers slightly acid to neutral, Height: 30 feet Width: 20 feet well-drained, moist soils; avoid dry Best in eastern Iowa sites with strong winds.

Pinus cembra—Swiss Height: 40 feet Width: 25 feet Best in eastern Iowa

Pinus flexilis—limber pine Height: 40 feet Width: 30 feet Resistant to winter burn

Pinus koraiensis—Korean pine Height: 40 feet Width: 30 feet Very hardy and adaptable to most White pine conditions —mugo pine Height: 15 feet Width: 20 feet Dwarf forms are available

Pinus ponderosa—ponderosa pine Height: 80 feet Width: 40 feet Best in western Iowa

Pinus resinosa—red or Norway pine Height: 50 feet Width: 25 feet Baldcypress Best in eastern Iowa Taxodium distichum— —eastern white pine Baldcypress Height: 75 feet Width: 50 feet Height: 50 feet Width: 30 feet Intolerant of road deicing salt spray Culture —Scotch pine Baldcypress, a deciduous conifer, Height: 60 feet Width: 50 feet grows best on sandy-loam soils Susceptible to pine wilt. with good moisture but tolerates extremes in moisture after it is firmly established in the landscape. Scotch pine Avoid alkaline soils. Canadian hemlock Tsuga—Hemlock Contact Organizations Culture Division/Iowa Tsuga species require good Department of Natural Resources drainage, adequate moisture, and Wallace Building, 502 E. 9th St. cool, acid soils; they perform Des Moines, IA 50319-0034 poorly on hot, dry, windy sites. (515) 281-5918 Hemlocks tolerate dense shade www.iowadnr.gov/forestry but prefer partial or light shade. Iowa State University Extension They are sensitive to air pollution Distribution Center Techny arborvitae and road deicing salts but will Ames, IA 50011 withstand heavy pruning. Thuja occidentalis— (515) 294-5247 Eastern arborvitae Recommended species www.extension.iastate.edu/store Tsuga canadensis— Culture Forestry Canadian hemlock Arborvitaes perform best on fertile, Ames, IA 50011-3221 Height: 70 feet Width: 40 feet moist, well-drained soils. They (515) 294-1168 Best in eastern Iowa prefer full sun but tolerate light www.forestry.iastate.edu shade. Choose cultivars resistant to winter browning. Horticulture Ames, IA 50011 Recommended cultivars (515) 294-2751 ‘Brandon’ www.yardandgarden.extension. Height: 12 feet Width: 4 feet iastate.edu Resistant to winter burn Trees Forever ‘Degroot’s Spire’ 770 7th Avenue, Marion, IA 52302 Height: 10 feet Width: 3 feet (319) 373-0650 Resistant to winter browning www.treesforever.org ‘Hetz Wintergreen’ Height: 20 feet Width: 7 feet Strong central leader

‘Holmstrup’ Height: 10 feet Width: 4 feet This institution is an equal opportunity Very winter hardy provider. For the full non-discrimination statement or accommodation inquiries, go ‘Techny’ to www.extension.iastate.edu/diversity/ext. Height: 12 feet Width: 8 feet Excellent dark green foliage Prepared by Jeff Iles, extension horticulturist, in conjunction with the Iowa Urban and Community Forestry Council.

File: Forestry 4